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Volume 46, 1913
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Art. XIII.—Descriptions of the Ova of some of the Lepidoptera of New Zealand.

[Read before the Wanganui Philosophical Society, 11th August, 1913.]

Plates I, II.

I Should first like to express my thanks to Mr. G. V. Hudson, of Wellington, whose kindness and help in identifying many of the species the eggs of which are described herein have been of no small assistance and encouragement to me. I am also greatly indebted to Mr. R. Murdoch, who gave me most valuable help in the preparation of the drawings and photographs. I shall always recognize a heavy debt of gratitude to both Mr. Hudson and Mr. Murdoch.

This paper is practically opening up a new branch of entomology in New Zealand. Hitherto the study of the eggs of our Lepidoptera has hardly been touched upon, though a beginning was made by the late Mr. Ambrose Quail, whose papers on the subject appear in the Transactions (vol. 33, p. 159, pl. ix; vol. 34, p. 226, pl. xiii). It has only been during the last few years that the importance of the subject has been recognized in England and on the Continent, and even in this short time an abundance of new and important scientific data has been published. Formerly entomologists confined themselves to elaborate and extensive descriptions of the adult insects only, considering the study of the larvae and ova as of no importance; these were small and often microscopically minute, and were therefore unworthy of notice. This idea is now exploded, and even more importance is being attached to the accurate descriptions of the primary forms of life and their development than to that of the adult forms.

Turning now to the paper itself, there are one or two items and terms that need some explanation. The eggs of all Lepidoptera are divisible into two classes or groups, known technically as “upright” and “flat” eggs, The shell is divisible into a base, walls, and apex. At the apex there is, as a rule, a microscopic depression, from the base of which minute canals lead into the egg, and carry the spermatozoa for the purpose of fertilization. This is known as the micropyle. The external characteristics of the micropyle generally take the form of a rosette of minute, delicately sculptured, elongated cells. We are now in a position to define the terms “upright” and “flat”: if the egg be so laid that the micropylar axis is horizontal to the surface on which it is laid it is called a “flat” egg, and if laid so that the micropylar axis is vertical to the surface on which it is laid it is termed an “upright” one. Although the micropyle is actually at the apex in an “upright” egg, yet, on the other hand, it is at one extremity of the long axis in “flat” eggs. The term “base,” as hitherto used by lepidopterists, is a doubtful quantity. It may be that side by which the egg is usually attached to the surface of the food plant or other object on which it may be deposited by the parent, or, on the other hand, the side opposite the micropyle may be termed the “base.” It follows, therefore, that we speak of a Noctuid egg as being laid on its base, and, to get rid of the anomaly, we speak of a Geometrid egg as being laid on its long side. We use the term “base” as being the side opposite the micropyle,

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as tending to preserve correctly the homologies of the egg-structures. Similarly, when describing the shape of certain eggs, the terms “longitudinal” and “transverse” sections have been used as meaning sections of the egg taken parallel or transversely to the micropylar axis.

As regards the size and sculpturing of the eggs of Lepidoptera, there is no need to go exhaustively into the subject here. To avoid confusion, it must be said that sometimes the eggs of the same species of moth or butterfly, and even individual eggs of a batch laid by the same parent, will differ slightly in size and sculpture: for instance, should an egg be ribbed with raised reticulations it may be found that in some eggs there are, say, fifteen such ribs, while in other eggs of the same moth, or of the same batch, there are seventeen, or perhaps only fourteen, of these reticulations. Where this occurs in the species described the limiting cases have been given. If, however, the variation is only very slight, the word “about” has been inserted before the statement. In many eggs the sculpturing is in the form of reticulations crossing and recrossing each other, and dividing the shell up into more or less deep figures: these depressions are termed “cells.” The shell of the egg of a lepidopterous insect consists of a thin pelliclo, more or less transparent, and sometimes opaque, and besides the main sculpturing sometimes gives rise to a secondary sculpturing, or it may be quite smooth, or more or less roughened. It must be remembered that all descriptions of the different portions of eggs mentioned herein are as seen through varying powers of the microscope, and that which may seem smooth when viewed under an inch power may turn out to be quite the opposite when seen through a half-inch or quarter-inch objective. A high power has in every case been used when describing such portions of the egg-structure.

The reason why such elaborate descriptions are needed is that in many cases the sole difference in the eggs of totally different species may lie entirely in the exact measurement of the eggs themselves, or even of only a portion of the eggs; or, again, in the slight variation in the sculpturing that is not at once apparent, but has to be sought out by means of series of microscopically minute and delicate measurements. Instances of such constantly occur among the Porina, Melanchra, and other groups.

Care has been taken to give all the more important synonyms of the species in every case, but it must not be concluded that the lists given are exhaustive; they are not. In almost every case reference has been made to Mr. R. W. Fereday's “Synonymic List of the Lepidoptera of New Zealand,”** where the complete lists of synonyms are given. Where the adult form of the ovum under consideration has been figured, reference to such has been given.

Porina cervinata Walk.

Elhamma cervinata Walk., Cat. Lep. Brit. Mus., Suppl. ii, p. 595. Porina vexata, ib., p. 597. P. cervinata Butl., Cat. Lep. N.Z., p. 5; Moyr., Trans. N.Z. Inst., 22, p. 208; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 329; Hudson, N.Z. Moths and Butterflies, p. 133, pl. 13, fig. 12.

I have only taken two females of this species. They are much attracted by light, and the ones I took were resting at the time on a street-lamp.

[Footnote] * Trans. N.Z. Inst., vol. 30, p. 326.

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Ovum.

Class.—Flat(?).

Shape.—Viewed from above, oval. Transverse section, circular.

Dimensions.—Length, 0·65 mm.; diameter, 0·58 mm.

Sculpture.—The whole egg, except the micropylar cap, is completely covered with thousands of extremely minute protuberances, twice as high as wide. These are transparent, and reflect the light from all directions, giving the egg a white-dusted appearance.

Micropyle.—Micropylar cap darker than rest of egg, free from protu berances, oval in shape, bounded by an irregular thin white marking, slightly raised. At either end of the micropylar cap is a small deep circular cell; these together comprise the micropyle. Measurements: Total length of micropylar cap, 0·09 mm.; total width of same, 0·05 mm.; length of same within white margin, 0·05 mm.; width ditto, 0·03 mm.; distance between micropylar cells, 0·04 mm. These measurements are necessary, as will be seen on comparing the eggs of other species of this genus with the one here described.

Shell.—Opaque; slightly shiny; very strong; sometimes gets much dented without any apparent harm to the embryo; retains its shape and colour after the larva has emerged.

Colour.—When fresh laid, pale dirty-cream colour, changing within twenty-four hours to black. No further change. Infertile eggs do not seem to turn black, for I obtained a number of eggs of the original pale-cream colour that proved to be infertile, and which did not turn black, but quickly collapsed. Other eggs that did turn black did not hatch, but this may have been due to causes other than being infertile.

Note.—The parent moth lays an enormous number of eggs; one that I had laid over 1,200 in two days, and in another case 300 were laid in a few hours. The eggs are laid in no particular manner, but are dropped anywhere quite indiscriminately, and are in no way attached to any object or to each other. Some eggs seemed to have large areas free of the protu berances before referred to, but on being examined under a high power this proved not to be so, the effect being produced, I think, by the collection of moisture between the elevations, which interfered, naturally, with their reflecting-powers, and, since they are transparent, gave the effect of bare patches on the shell. The larva eats its way out at the micropylar end, but otherwise does not injure the shell in any way; it is very sluggish in its movements. Period of incubation, about thirty-one days.

(Described, 10th October, 1912.)

Porina umbraculata Guén.

Pielus umbraculatus Guén., Ent. Mo. Mag., 5, p. 1 (1868). Porina umbraculata Butl., Cat. Lep. N.Z., p. 5; Meyr., Trans. N.Z. Inst., 22, p. 209; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 330; Hudson, N.Z. Moths and Butterffies, p. 134, pl. 13, fig. 14.

Very common at Wanganui, and can be taken in great abundance on lamp-posts on a close night just before rain.

Ovum.

Class.—Flat(?).

Shape.—As seen from above, oval. Transverse section circular. Micro pylar end slightly flattened.

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Dimensions.—Length, 0·65–0·58 mm.; diameter, 0·58 mm.

Sculpture.—Similar to that of Porina cervinata. The protuberances are slightly smaller.

Micropyle.—Similar to that of Porina cervinata, only the white margin around the platform is wanting. The protu berances cease within 0·02 mm. of the platform. The dimensions are: Length of platform, 0·05 mm.; width of platform, 0·03 mm.; distance between cells, 0·02 mm.

Shell.—Opaque; slight sheen; very strong; retains its shape and colour after the emergence of the larva. Gets much dented without any apparent harm to the larva.

Colour.—When fresh laid, pale cream, turning to steel-grey, and in twelve hours to black with very slight green tinge.

Note.—The same remarks re protuberances, infertile eggs, and mode of laying apply here as to Porina cervinata. Lots of 626, 503, 343, 205 eggs obtained; in all cases all these eggs were laid in one night. Laid, 3rd November; hatched, 5th December = thirty-two days.

(Described, 5th November, 1912.)

Porina characterifera Walk.

Hepialus characterifera Walk., Cat. Lep. Brit. Mus., Suppl. ii, p. 594 (1865); Butl., Cat. Lep. N.Z., p. 5. Oxycanus impletus, ib., p. 598. Porina characterifera Meyr., Trans. N.Z. Inst., 22, p. 208; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 329; Hudson, N.Z. Moths and Butterflies, p. 12, pl. 13, fig. 11.

Several of this rare and beautiful species were caught on Mount Egmont (elevation 3,000 ft.) in January of this year (1913). It was very plentiful, flying high and extremely swiftly. Mr. Hudson, in his “New Zealand Moths and Butterflies,” records four only as having been caught; but many more have, I think, been caught since. The moths did not seem to be at all attracted by light.

Ovum.

Class.—Flat (?).

Shape.—Oval. Transverse section circular.

Dimensions.—Length, 0·88 mm.; diameter, 0·65 mm.

Sculpture.—Similar to that of the egg of P. cervinata.

Micropyle.—The micropylar platform is oval and slightly raised, with a shallow moat surrounding it; darker than rest of egg, and covered with the small protuberances that cover the rest of the egg. The micropyle consists of two small deep circular cells about 0·01 mm. apart.

Shell.—Opaque; strong; slight sheen; retains its shape and colour after emergence of the larva. Gets very dented in some cases without apparent harm to embryo.

Colour.—When fresh laid, pale green, turning within twelve hours to black. No further change.

Note.—Laid indiscriminately, at fairly long intervals, and not attached in any way to plants or other objects. The remarks about the infertile eggs of P. cervinata apply here also. The moth lays an enormous number of eggs, though only thirty-three were obtained. Period of incubation is about thirty days.

(Described 18th January, 1913.)

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Nyctemera annulata Boisd.

Leptosoma annulatum Boisd., Voy. de l'Astr., Ent., 5, p. 197. Nyctemera doubledayi Walk., Cat. Lep. Brit. Mus., 2, p. 392. N. annulata Butl., Cat. Lep. N.Z., p. 4; Meyr., Trans. N.Z. Inst., 22, p. 218; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 331; Hudson, N.Z. Moths and Butterflies, p. 2, pl. 4, figs. 1, 2.

One of our commonest moths in Wanganui during early and late summer. It is to be seen throughout the day, but is most plentiful in the early morning.

Ovum. Plate I, fig. 7.

Class.—Upright.

Shape.—As seen from above, circular. Vertical section: Base flat; sides diverging to the equator, converging above; top half of egg somewhat pointed; extreme top flat.

Dimensions.—Height, 0·70 mm.; diameter, 0·84 mm.; diameter of flat top, 0·12 mm.

Sculpture.—The shell is covered with minute olevations joined by exceedingly fine reticulations, forming five-, six-, and seven-sided figures, all more or less irregular in shape. Diameter of cells, about 0·02 mm. Mr. Ambrose Quail* says that he has come across batches of these ova which were quite smooth. I have noticed the same thing myself, but when the eggs were properly illuminated and viewed with a high power the cell-structure became quite plain.

Micropyle.—Situated in rosette of nine elongated cells. The cells of the network immediately surrounding the rosette are somewhat elongated in a direction radial from the micropyle. Diameter of rosette, 0·06 mm.; diameter of micropyle, 0·01 mm.

Shell.—Strong; transparent; shiny; roughened and slightly pitted within the cells when viewed with a high power.

Colour.—When fresh laid, pale yellow, intensifying in a day or so to deep yellow. In thirteen days a small brown area appears to one side of the micropyle, and in another day or so the whole egg changes to light grey, and the larva is plainly distinguishable. The long black hairs of the larva are very plain, and give the egg a most curious striated look.

Note.—Laid in small batches of ten or more. Not very firmly attached to food plant, and but slightly to each other, most often not touching at all. In a few days after being laid the upper surface of the egg gets slightly dented. One hundred and fifteen eggs obtained from one moth. Laid, 11th November; hatched, 27th November = sixteen days.

(Described, 17th November. 1912.)

Melanchra ignana Walk.

Hadena lignana Walk., Cat. Lep. Brit. Mus., 11, p. 543. Xylophasia morosa Butl., Cist. Ent., 2, p. 543. Mamestra lignana Meyr., Trans. N.Z. Inst., 19, p. 26; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 335. Melanchra lignana Hudson, N.Z. Moths and Butterflies, p. 26, pl. 5, fig. 19.

This pretty moth is very common at Wanganui during the early summer.

[Footnote] * Trans. N.Z. Inst., vol. 34, p. 228.

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Ovum. Plate II, fig. 6.

Class.—Upright.

Shape.—Hemispherical; top and bottom flattened, and of equal area.

Dimensions.—Diameter, 0·75–0·79 mm.; height, 0·58 mm.; diameter of top or bottom, 0·28 mm.

Sculpture.—Very pronounced. From the micropyle about fourteen high, semi-transparent, very thin ribs radiate towards the equator, converging below. At a slight distance from the equator, on the upper portion, of the egg, they are joined by other similar but alternate ribs, making about twenty-six longitudinal ribs in all. Finer reticulations traverse the egg at right angles to the micropylar axis, continuing up the sides and over the longitudinal ribs. The cells so formed are deep, show modified hexagon formation, and are longest in the direction parallel to the transverse reticulations. The dimensions of the cells around the equator are — length, 0·09 mm.; width, 0·02 mm.; depth, 0·02–0·03 mm. These, of course, diminish in length as they approach the micropyle. The base of the egg is slightly reticulated by the continuance of the longitudinal ribs. The number of longitudinal ribs is not constant.

Micropyle.—Situated in a rosette of ten to fourteen elongated cells surrounded by a band of fifteen hexagonal cells from which the longitudinal ribs originate. The rosette is raised within a depression in the top of the egg, and the micropyle is sunk crater-like in it. Measurements: Diameter of micropyle, 0·01 mm.; diameter of rosette, 0·08 mm.; length of hexagonal cells surrounding rosette 0·04 mm., width 0·03 mm.

Shell.—Strong; transparent; highly glossy; smooth within cells.

Colour.—Pearly white. In about a week a narrow band of light brown surrounds the egg just above the equator, and a small irregular area of light brown covers the micropyle. Four days later the light brown intensifies to a much darker shade, and the rest of the egg turns a light grey. At this stage the larva can be seen within the egg. Just before hatching the reticulations become white and very distinct. Infertile eggs turn slightly yellow, and collapse.

Note.—Laid singly and in small lots of four or five. Well attached to object, but not to each other. In one batch of fifty-six the eggs were arranged in neat regular rows, but not touching each other. Laid in November and December. The period of incubation is about eleven days. Larva emerges through the top of the egg to one side of the micropyle, and makes its first meal off the shell.

(Described, 17th November, 1912.)

Melanchra mutans Walk.

Hadenda mutans Walk., Cat. Lep. Brit. Mus., 11, p. 602. H. lignifusca Walk., ib., p. 603. Mamestra angusta Feld., Reise der Nov., pl. cix, fig. 18. M. mutans Meyr., Trans. N.Z. Inst., 19, p. 17; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 333. Melanchra mutans Hudson, N.Z. Moths and Butterflies, p. 18, pl. 4, figs. 34, 35, 36.

One of our commonest moths in Wanganui; taken in great numbers at “sugar,” and much attracted by light.

Ovum. Plate II, figs. 1 and 5.

Class.—Upright.

Shape.—Transverse section circular. Longitudinal section: Base flat, top slightly flattened, sides bulged, equator equidistant from the poles.

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Dimensions.—Height, 0·44 mm.; diameter, 0·61—0·65 mm.

Sculpture.—Similar to that of M. insignia. Exceptions: Total number of ribs, 33—40; dimensions of cells at equator—length 0·05 mm.; width 0·02 mm. The length of the cells is taken at right angles to the longitudinal ribs.

Micropyle.—A small deep circular cell situated in the centre of a rosette of'eleven elongated cells. The rosette is slightly elevated, and is surrounded by a band of about twenty elongated cells, about twice as long as broad, lengthened in direction radial from the micropyle, dimensions being—length about 0·05 mm., width about 0·03 mm. There is a second band of irregular pentagonal and hexagonal cells from which the main ribs originate. Diameter of micropyle, 0·01 mm.; rosette, 0·08 mm.

Shell.—Transparent; fairly strong; shiny; slightly roughened within reticulations.

Colour.—When fresh laid, creamy white, changing in about four days to a light-brown mottling on upper half of egg. On the fifth day the upper surface of the egg (above the equator) is light brown with small creamy-white areas surrounding the micropyle. Below the equator the colour remains pearly white till near the date of hatching. In seven days the colour is a dark blackish-grey, a slight mottling still apparent. Just before hatching the colour gets much lighter in shade, and the creamy, area below the equator turns a very light grey. The hairs of the larva are very plain at this stage, and the reticulations become white and very plain. Infertile eggs collapse without undergoing changes in colour.

Note.—These eggs are laid in batches in neat regular rows; sometimes there are two, and even three, tiers of eggs in one batch. Well attached to food plant, and slightly to each other. Batches obtained in April and October to December, consisting of from 180 to 92 eggs. Period of incubation fourteen to eleven days, according to weather. The parent moth does not always confine herself to laying only one batch, sometimes laying two, or even three, or more. When the eggs are first laid they are very soft, and are often pressed into irregular shapes by their neighbours, but this does not seem to affect them in any way. The larvae emerge through the top of the egg to one side of the micropyle, and make their first meal off the empty shell. I have found hundreds of batches, of these eggs on the underside of the leaves of the white magnolia, and several batches on the underside of the leaves and on the bark of the red flowering gum. The moth also often lays her eggs on windows and walls of houses and other seemingly most unsuitable places.

(Described, 17th April, 1912.)

I add here descriptions of eggs belonging to two varieties of this moth (Melanchra mutans) which are very common. These differ quite enough to make one believe at first sight that they belong to different species.

Variety A.

Ovum.

The main differences in this egg are as follows:—

Dimensions.—Height, 0·37 mm.; diameter, 0·65 mm.

Sculpture.—Total number of ribs, 43—45; cells about 0·02 mm. square. Ribs 0·02—0·03 mm. apart at equator. The cells here do not show the modified hexagon form.

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Micropyle.—Situated in rosette of about seventeen elongated cells. Diameter of rosette, 0·06 mm.; diameter of micropyle, 0·02 mm.

Colour.—When fresh laid, pale green; this slightly intensifies till the fourth day, when a light-brown ring appears around the equator and a large irregular area of light brown caps the egg. The brown areas are spotted with numerous small light-coloured areas, and get much darker in colour till a day or so before hatching, when they turn a blackish-grey, and then get much lighter in colour—in fact, almost a light grey. The hairs of the larva are most conspicuous. The green areas do not change till the day before hatching, when they assume a very light grey tint. Infertile eggs remain green, and collapse.

Note—Period of incubation, from nine to fourteen days. Eggs laid in batches of from 200 to 67.

(Described, 10th November, 1912.)

Variety B.

Ovum.

The following important characteristics distinguish this egg:—

Shape.—Transverse section circular. Longitudinal section: Sides regular and bulged, top and bottom flat and of equal area. These eggs have the appearance of having been subjected to pressure from above and below between two flat surfaces.

Dimensions.—Height, 0·42 mm.; diameter, 0·63 mm.; diameter of top or bottom, about 0·37 mm.

Sculpture.—About nineteen main ribs. Total number of ribs about thirty, whose distance apart at the equator is about 0·06 mm. Transverse reticulations are about 0·03 mm. apart. The cells show modified hexagon form.

Micropyle.—There is no second band of hexagonal cells surrounding the micropyle. The following measurements are important: Diameter of rosette, 0·07 mm.; diameter of micropyle, 0·015 mm.; length of hexagonal cells surrounding rosette, 0·03 mm.; width of ditto, 0·02 mm.

Colour.—Light green. The surface of the egg above the equator is peppered with numerous small light-brown spots; later the reverse is the case, the surface being dark brown with a few small scattered light-brown areas, which as the rest intensifies are in most cases entirely lost.

Note.—Laid in no definite order, but in large scattered groups of about 100 eggs. Infertile eggs remain green, and collapse.

(Described, 27th November, 1912.)

The eggs of M. mutans seem to be very subject to attacks of parasites, and I have found thousands of the eggs destroyed in this way.

Melanchra insignis Walk.

Euplexia insignis Walk., Cat. Lep. Brit. Mus., 33, Suppl. iii, p. 724. Xylina turbida, ib., p. 754; Butl., Cat. Lep. N.Z.,. p. 9. Mamestra ‘insignis Meyr., Trans. N.Z. Inst., 20, p. 45; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 333. Melanchra insignis Hudson, N.Z. Moths and Butterflies, p. 16, pl. 4, figs. 29, 30; Philpott, Cat. Southland Lep., Trans. N.Z. Inst., 33, p. 169.

This moth can be taken around Wanganui at “sugar” in great abundance. It is also attracted by light, and is very common about houses and street-lamps during the summer.

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Ovum. Plate I, fig. 8.

Class.—Upright.

Shape.—As seen from above, circular. Transverse section: Bottom flat; sides extending outwards, downwards, and inwards. Top half of egg slightly pointed; extreme top flattened.

Dimensions.—Diameter (at equator), 0·65 mm.; height, 0·42 mm.

Sculpture.—Strong. Strong reticulations or ribs radiate from the micropyle, and diverge towards the equator, converging below. About one in three of these ribs coalesce with another slightly above the shoulder of the egg, but there is irregularity in this respect. There are about forty-one ribs in all, of which about fifteen meet the micropylar. cap. The ribs are intersected at right angles by finer reticulations, forming well-defined almost square cells, which under a high power seem to be modified hexagons. The distance between the ribs at the equator is 0·05 mm.

Micropyle.—Consists of a small cell within a rosette of nine, sometimes ten, large elongated cells. The rosette is slightly raised, the elongated cells forming the sides of the elevation; at the top is the micropyle, but sunk crater-like. A band of elongated cells, slightly larger than those forming the rosette, surround the micropylar elevation, and from these cells the main ribs on the egg originate. Measurements are: Micropyle, 0·01 mm.; rosette or micropylar elevation, 0·08 mm. diameter.

Shell.—Fairly strong; shiny; transparent; slightly roughened within cells.

Colour.—When fresh laid, pale green. On the second day the top half of the egg is a light brown except for a large irregular area to one side of the micropyle, and not including it, of the original light green. The under half of the egg remains light green till just before hatching. The brown gradually intensifies, and small dark-coloured spots are scattered over its surface. The irregular green area mentioned above gets smaller as the brown encroaches upon it, and finally splits up into two and sometimes three very small areas. A few days before hatching the light-green areas remaining and on the under half of the egg turn light brown, and the larva can be clearly seen. The whole egg now becomes very dark in colour.

Note.—Well attached to food plant and to each other, though most often the eggs are laid in large spread-out batches in which they do not touch each other. The batch described consisted of 109 eggs. The larvae emerge through the side of the shell, and make their first meal off it. Laid, 13th November; hatched, 24th November = eleven days.

(Described, 13th November, 1912.)

Melanchra composita Guén.

Cloantha composita Guén., Noct., 6, p. 114. Mamestra composita Meyr., Trans. N.Z. Inst., 19, p. 22; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 334. Melanchra composita Hudson, N.Z. Moths and Butterflies, p. 22, pl. 5, figs. 8, 9.

This moth is very common throughout the year in the Wanganui district.

Ovum. Plate II, fig. 2.

Class.—Upright.

Shape.—Seen from above, circular. Longitudinally oval. Micropylar end slightly larger than its nadir. Sides somewhat compressed.

Dimensions.—Height, about 0·70 mm.; diameter, at micropylar end, 0·58 mm.

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Sculpture.—Extremely fine. Minute reticulations form, a network of irregular four-, five-, and six-sided cells of about 0·02 mm. diameter. Cells surrounding micropyle lengthened in direction radial from the micropyle. Reticulations very hard to distinguish, even under high powers.

Micropyle.—Situated in rosette of elongated pear-shaped cells. Diameter of rosette, about 0·10 mm. Bands of four- and five-sided cells surround the rosette; they are rather elongated, and merge into the common network. Micropyle very indistinct.

Shell.—Fairly strong; transparent; highly glossy; smooth within cells.

Colour.—When fresh laid, creamy white, changing in a day or two to a distinct cream colour. Later the egg assumes a pink tint, and just before hatching turns a slate-blue, while the larva is plainly seen. Infertile eggs turn a light yellow, and collapse.

Note.—Laid in small batches in rows in crevices of box, one row above another. The eggs get very dented soon after being laid; in some cases the dents extend from the micropyle to the base, and give the egg a very strongly longitudinally ribbed appearance. Very strongly attached to each other, and to the box but slightly. Batches of twenty-eight and fifty-five eggs obtained. Laid in October and November. Period of incubation, about seventeen days. The larva eats its way through the micropylar end, and in some cases makes its first meal off the empty shell.

(Described, 2nd October, 1912.)

Melanchra dotata Walk.

Dasypolia dotata Walk., Cat. Lep. Brit. Mus., 11, p. 522; Butl., Cat. Lep. N.Z., p. 8. Mamestra dotata Meyr., Trans. N.Z. Inst., 19, p. 24; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 334. Melanchra dotata Hudson, N.Z. Moths and Butterflies, p. 24, pl. 5, fig. 16.

I have only succeeded in obtaining three specimens of this moth, and have reason to believe that it is rare around Wanganui. Mr. Hudson records two specimens as having been caught.

Ovum. Plate I, fig. 1.

Class.—Upright.

Shape.—Semispherical; base flat; top flattened slightly.

Dimensions.—Height, 0·54 mm.; greatest diameter, 0·82 mm.

Soulpture.—Strong. Similar to that of M. insignis. The following are the chief distinctions: Longitudinal ribs very pronounced, forty-one in number. The shell is broken up by transverse reticulations into fairly deep quadrilateral cells. A network of pentagonal and hexagonal cells surrounds the micropyle.

Micropyle.—Situated in a rosette of six elongated cells. Rosette about 0·04 mm. diameter, and surrounded by the network of cells mentioned above.

Shell.—Very fragile; transparent; shiny; slightly roughened within cells.

Colour.—Very pale green. In about a week a small brown spot is discernible on either side of the micropyle; later more such spots appear, also large irregular areas of darker green. Two days after this a number of small black spots surround the micropyle, while a larger reddish-brown

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area appears to one side of it. The hairs of the larva are first to be seen, and later the larva itself is plainly distinguishable. Infertile eggs turn a slightly darker shade of green, and in a week or so collapse.

Note.—Laid in large flat bunches in irregular rows. Batches of 92 and 140 eggs obtained. Strongly attached to box and slightly to each other. Laid, 15th September; hatched, 30th September = fifteen days. The larva emerges through the top of the. egg, and makes its first meal off the shell.

(Described, 15th September, 1912.)

Orthosia immunis Walk.

Taeniocampa immunis Walk., Noct., 430. Cerastis innocua, ib., 1710. Agrotis acetina Feld., Reise Nov., pl. cix, fig. 6. Orthosia immunis Meyr., Trans. N.Z. Iast., 19, p. 30; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 335; Hudson, N.Z. Moths and Butterflies, p. 7, pl. 5, fig. 29.

Fairly common. To be taken in great numbers at “sugar” and on street-lamps.

Ovum.

Class.—Upright.

Shape.—Transverse section circular (as a rule). Vertical section: Base flat; sides bulging outwards and curving in towards the top; top flattened Diameter of top, 0·23 mm.

Dimensions.—Diameter, 0·65—0·70 mm.; height, 0·47—0·55 mm.

Sculpture.—Strong. High reticulations or ribs radiate from the micropylar cap to the equator, converging below. About one in two of the ribs coalesce with another a little above the shoulder of the egg, and there is irregularity in this respect; in more than one instance three ribs coalesce. Thirteen to seventeen ribs meet the micropylar cap. There are from thirty-one to thirty-seven ribs in all. Between the ribs equidistant finer reticulations form quadrilateral cells about twice to three times as broad as long, measurements being—width, 0·05—0·06 mm.; length, about 0·02 mm. Height of longitudinal ribs, 0·01—0·03 mm.; distance apart at equator, 0·05—0·06 mm. Base heavily wrinkled, but not sculptured.

Micropyle.—A deep moat surrounds a correspondingly high eruption which bears the micropyle, crater-like. The micropyle is a deep circular cell 0·01 mm. diameter. The eruption is ribbed longitudinally with fine reticulations forming a rosette of thirteen elongated cells surrounding the micropyle; from these the main ribs or reticulations of the egg originate. The floor of the moat is composed of a band of eighteen hexagonal cells, 0·045 mm. long by 0·02 mm. wide, lengthened in a direction radial from the micropyle. Depth of moat or height of eruption, 0·04 mm.; diameter of eruption, 0·07 mm.; width of moat, about 0·05 mm.

Shell.—Very strong; transparent; shiny; roughened, and slightly wrinkled between reticulations.

Colour.—When fresh laid, white. The second day there is a slight cream tint, changing later to light yellow. On the fourth day the upper half of the egg is lightly mottled with very light brown. On the fifth day there is a distinct broad light-brown band surrounding the egg just above the equator, and a large irregular brown patch covers the micropylar area. The brown coloration now greatly intensifies in shade, the micropylar area being slightly lighter in colour than the equatorial belt. The day before hatching all the light colouring on the shell between the brown-areas turnss

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black, the brown areas get very dark, while the reticulations show up white and sharp, and the larva can be plainly distinguished within the egg. In most cases the brown equatorial belt is broken by a small arm of light yellow joining the top and bottom yellow areas, and sometimes the brown micropylar area extends one or more arms of brown joining it to the equatorial belt. Infertile eggs remain a creamy tint, and quickly collapse.

Note.—Laid in crevices in large uneven batches of sixty eggs or more. Well attached to object, but slightly, if at all, to each other. Batches of sixty and seventy-eight eggs obtained. 115 and 302 eggs obtained from one moth. Laid in November. Period of incubation, eleven days. The larva emerges through the top of the egg to one side of the micropyle, and makes its first meal off the empty shell, sometimes giving its neighbours a help too.

(Described, 17th November, 1912.)

Bityla defigurata Walk.

Xylina defigurata Walk., Cat. Lep. Brit. Mus., 33-, Supp., p. 756. Bityla thoracica, ib., p. 869; Butl., Cat. Lep. N.Z., p. 10. B. defigurata Meyr., Trans. N.Z. Inst., 19, p. 31; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 335; Hudson, N.Z. Moths and Butterflies, p. 29, pl. 5, fig. 33.

Fairly common. Can be taken in great numbers at “sugar.”

Ovum.

Class.—Upright.

Shape.—Spherical; sides much bulged; top slightly flattened. Many eggs, owing to pressure from their neighbours while still soft, are somewhat forced out of their true circular form.

Dimensions.—Diameter, 0·61 mm.; height, 0·51 mm.

Sculpture.—Strong corrugations or ribs radiate from the micropylar area to the equator, converging below. About one in two of the ribs coalesce with another midway between the equator and the micropyle. There are from thirty-three to thirty-six ribs in all, about seventeen of which reach the micropylar area. Between the ribs finer equidistant reticulations apparently form quadrilateral cells, but examined with a high power it is found that they are really modified hexagons with strong longitudinal sides. These transverse reticulations are about 0·02 mm. apart. The longitudinal ribs are about 0·04 mm. apart at the equator.

Micropyle.—Situated in a rosette of twelve elongated cells, which is surrounded by a band of hexagonal cells, longer than broad, lengthened in a direction radial from the micropyle, very irregular in size, and about sixteen to eighteen in number. The micropyle is depressed crater-like within the rosette, which is raised slightly. Diameter of micropyle, 0·005 mm.; diameter of rosette, 0·06 mm.; length of hexagonal cells surrounding the rosette, 0·03 mm.; width, about 0·02 mm.

Shell.—Strong; transparent; shiny; very slightly roughened within cells when viewed with a high power.

Colour.—When fresh laid, pale creamy-white. In a few days a lightbrown ring appears on the upper surface of the egg just above the equator, and an irregular area of light brown covers the micropylar cap. The light brown intensifies to a beautiful rich russet-brown, and at the same time encroaches more upon the egg. The greater part of the brown area at the

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micropylar cap is to one side of the micropyle itself, and in some oases connects with the brown equatorial belt. The day before hatching the whole of the egg is marbled with different shades of brown, and the larva can be seen making slight movements within the egg, its black hairs being very conspicuous. Infertile eggs turn a light pink, and collapse.

Note.—Laid in batches in neat and regular rows. Well attached to food plant, and slightly to each other. Laid in December. Period of incubation is about nine days. The larva makes its first meal off the empty egg-shell.

(Described, 13th December, 1912.)

Plusia chalcites Esp.

Phusia eriosoma Dbld., Dieff. N.Z., p. 285; Butl., Cat. Lep. N.Z., p. 9, tab. 3, figs. 1, 2; Meyr., Trans. N.Z. Inst., 19, p. 36; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 336. P. chalcites Hudson, N.Z. Moths and Butterflies, p. 35, pl. 6, fig. 3.

This beautiful moth is very common in Wanganui throughout the summer, and may often be caught hovering over the garden-flowers in the hot sunshine. The larva has become a regular pest to the flower-gardener. The parent moth lays its eggs on the buds of certain large flowers, such as dahlias, sunflowers, asters, and the like. The young larva burrows into and feeds on the heart of the flower, and when finished with one betakes itself to another, in this way spoiling many a large, seemingly perfect bloom, but which on closer examination bears a huge caterpillar snugly coiled up in its very heart. The pupa is encased in a light silken cocoon sandwiched between two or more leaves.

Ovum. Plate I, fig. 10.

Class.—Upright.

Shape.—A flattened sphere, wider at equator than in vertical section. Base flat; top flattened; micropyle raised.

Dimensions.—Height, 0·33 mm.; diameter, 0·63 mm.

Sculpture.—Strong corrugations or ribs radiate from the micropyle towards the equator, converging below. About two in three of the ribs coalesce with another a little above the shoulder of the egg, but there is irregularity in this respect. About thirteen main ribs reach the micropylar area, and there are about forty ribs in all; these are about 0·02 mm. apart at the equator. Between the ribs finer equidistant reticulations form almost square cells, fairly deep.

Micropyle.—Consists of a small circular cell in midst of a rosette of seven elongated, pear-shaped cells. The rosette is surrounded by two bands or belts of hexagonal cells. The walls of these form the origin of the main ribs.

Shell.—Very fragile; transparent; shiny; smooth within cells.

Colour.—When fresh laid, a pale cream, which, if anything, gets slightly lighter. The larva can be seen within the shell before hatching. Infertile eggs quickly collapse.

Note.—Laid singly. Are well attached to food plant, and in most cases cannot be removed without breakage. Laid in May, and even as early as March. Period of incubation, about a month. The larva emerges at micropylar end.

(Described, 20th May, 1912.)

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Rhapsa scotosialis Walk.

Herminia lilacina Butl., Proc. Zool. Soc. Lond., 1877, p. 388, pl. xlii, fig. 11. Rhapsa scotosialis Walk., Cat. Lep. Brit. Mus., 34, Supp., p. 1150; Butl., Cat. Lep. N.Z., p. 10; Meyr., Trans. N.Z. Inst., 19, p. 38; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 337; Hudson, N.Z. Moths and Butterflies, p. 36, pl. 6, figs. 5, 6.

This little moth is extremely common about Wanganui throughout the year.

Ovum. Plate I, fig. 12.

Class.—Upright.

Shape.—Transverse section circular. Longitudinal section: Base flat; sides bulging outwards just above the base and then converging at an angle of 45 degrees, making the upper surface of the egg conical in shape.

Dimensions.—Height, 0·49 mm.; greatest diameter, 0·75—0·77 mm.

Sculpture.—The shell is covered with minute white elevations 0·005 mm. diameter, joined by slender reticulations, forming extremely shallow regular hexagonal cells 0·01 mm. diameter. Base smooth.

Micropyle.—Consists of a star-shaped cell surrounded by a rosette of twelve elongated cells. The small white elevations before referred to surround the outer margin of the rosette.

Shell.—Strong; transparent; shiny; slightly roughened or velvety surface.

Colour.—Very light green turning to a steel-grey, and later to a slaty colour. In about a week the colour is light yellow, and soon after the egg is marbled with reddish-brown markings. A few days before hatching the larva can be seen within the egg quite plainly. Infertile eggs turn a light blue, and collapse.

Note.—Laid singly. Well attached to object. The micropylar end collapses about a week after the egg is laid, forming a deep depression in the top of the egg. Batches of eggs obtained in April, July, September, October, November, and December. Period of incubation, about three weeks. The larva emerges at micropylar end of egg, and sometimes makes a meal off the shell.

(Described, 29th April, 1912.)

Euchoeca rubropunctaria Dbld.

Ptychopoda rubropunctaria Dbld., Dieff. N.Z., 2, p. 287. Hippolyte rubropunctaria Meyr., Trans. N.Z. Inst., 16, p. 60; ib., 17, p. 63. Epicyme rubropunctaria Meyr., ib., 18, p. 184; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 338. Euchoeca rubropunctaria Hudson, N.Z. Moths and Butterflies, p. 51, pl. 6, fig. 35.

This pretty little moth is scarce in the Wanganui district.

Ovum.

Class.—Flat.

Shape.—Wafer-like. Longitudinal section oval; micropylar end flattened, broader than its nadir. Transverse section oval; top and bottom much flattened; micropylar end higher than its nadir.

Dimensions.—Length, 0·56—0·58 mm.; width, 0·37 mm. (at micropylar end); height, 0·33 mm. when laid, and a week or so later about 0·28 mm.

– 79 –

Sculpture.—Coarse. Reticulations forming fairly regular hexagonal cells about 0·04 mm. diameter arranged in irregular rows from end to end of egg.

Micropyle.—Situated within a large cell. Slightly raised. Total diameter, 0·05 mm. Very indistinct.

Shell.—Strong; transparent; shiny; roughened within cells.

Colour.—Yellow. Small orange areas appear on the shell in five or six days, and gradually turn to bright reddish-orange. A small black spot appears at micropylar end a day or so previous to the hatching of the egg. The larva can be seen within the egg just before hatching.

Note.—Laid singly. Hardly, if at all, attached to object. The egg soon gets a very dented appearance after being laid, and the top surface collapses, forming a deep oval depression in the egg. Laid in September. Seventeen eggs obtained. Period of incubation, about sixteen days. The larva emerges at micropylar end.

(Described, 20th September, 1912.)

Asaphodes megaspilata Walk.

Larentia megaspilata Walk., Cat. Lep. Brit. Mus., 24, p. 1198; Butl., Cat. Lep. N.Z., p. 14; ib., Cist. Ent., 2, p. 502. Harpalyce megaspilata Meyr., Trans. N.Z. Inst., 16, p. 63. Probolaea megaspilata Walk.: Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 338. Asaphodes megaspilata Walk., Hudson's N.Z. Moths and Butterflies, p. 55, pl. 7, figs. 17, 18, 19, 19a, 20; Quail, Trans. N.Z. Inst., 34, p. 235.

This little species is frequently met with in Wanganui during the summer, and is easily obtained during the daytime by beating thick bushes and creepers.

Ovum. Plate II, fig. 3.

Class.—Flat.

Shape.—Viewed from above, oval; micropylar end slightly flattened and a little broader than its nadir. Transverse section: Micropylar end higher than its nadir, which is well rounded; top and bottom flattened.

Dimensions.—Length, 0·58–0·61 mm.; width, 0·44–0·47 mm.; height, 0·37–0·42 mm.

Sculpture.—Strong. Shell covered with a network of fairly regular shallow hexagonal cells, deepest in the centre. Cells about 0·04 mm. diameter. The reticulations are surmounted by numbers of very minute elevations or pimples. These elevations are most numerous at the micropylar end, and do not confine themselves to the reticulations, but are to be found on the floor of the cells also.

Micropyle.—Consists of a rosette of six small cells surrounded by a band of irregular cells somewhat lengthened in a direction radial from the micropyle. Rosette slightly elevated, 0·06 mm. diameter, and slightly darker in colour than rest of egg. The cells immediately surrounding the micropyle are smaller than on other parts of the egg.

Shell.—Strong; transparent; glossy; slightly roughened within cells.

Colour.—When fresh laid, white, sometimes with a very faint green tinge. In about four days the base of the egg changes to reddish-brown and later to a terra-cotta, shading off towards the micropylar end, which turns a light yellow. Four days before hatching a small black area appears

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at the micropylar end, and shortly after the egg gets mottled and striped with black. At this stage the larva can be seen making slight movements within the shell. Infertile eggs turn yellow, and collapse.

Note.—Laid singly in crannies. Well attached to object. Fifty-one and forty-three eggs obtained from different moths. Laid in October, November, and December. Period of incubation, about thirteen days. Larva emerge micropylar end.

(Described, 15th October, 1912.)

Venusia verriculata Feld.

Cidaria verriculata Feld., Reise der Nov., 5, pl. cxxxi, fig. 20. Phibalapteryx verriculata Butl., Proc. Zool. Soc. Lond., 1877, p. 396. Panopoea verriculata Meyr., Trans. N.Z. Inst., 16, p. 62. Paneyma verriculata Fereday, List. N.Z. Lep., Trans. N.Z. Inst., 30, p. 338. Venusia verriculata Hudson, N.Z. Moths and Butterflies, p. 53, pl. 6, figs. 30, 31.

This beautiful species is very plentiful at Wanganui.

Ovum.

Glass.—Flat.

Shape.—Oval. Much flattened on top and bottom surfaces, though slightly convex; sides much bulged. Micropylar end slightly broader than its nadir.

Dimensions.—Length, 0·75–0·79 mm.; width, 0·58 mm.; height, 0·44 mm.

Sculpture.—The reticulations form a network of irregular hexagonal and pentagonal cells about 0·04 mm. diameter, but around the micropyle the sculpturing is very confused and indistinct.

Micropyle.—Situated in a rosette of about ten elongated cells; surrounded by a band of small hexagonal cells. Diameter of rosette, about 0·08 mm.

Shell.—Strong; shiny; transparent; larva plainly seen a day or so before hatching.

Colour.—Bright green when first laid. In a few days they change to a red-brown with green areas, which later resolves into large irregular areas of red-brown and green. The margins of the areas are quite distinct, the colours not blending into each other. The red-brown areas now gradually increase in size, and get a brilliant red. A day or so before hatching a large brown area (the caput) appears at the micropylar end, and soon splits up into seven small brown areas; the red colouring collects at the base, leaving the rest of the egg a brownish-red. This egg makes a most beautiful object for the low-power microscope.

Note.—Laid end to end in batches in neat parallel rows. The numbers of eggs in different batches differ greatly, some moths laying all their eggs in one batch, others in several small batches, and others again lay their eggs singly. Two hundred eggs were obtained from one moth. The eggs are firmly cemented to food plant, but not to each other. In about a week after being laid the top of the egg collapses a great deal, forming fairly deep oval depressions. Laid in April and October. Period of incubation, about fifteen days.

(Described, 21st April, 1912.)

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Elvia glaucata Walk.

Elvia glaucata Walk., l.c., p. 1431; Butl., Cat. Lep. N.Z., p. 18, and Cist. Ent., 2, p. 509; Meyr., Trans. N.Z. Inst., 16, p. 65; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 339; Hudson, N.Z. Moths and Butterflies, p. 46, pl. 6, figs. 23, 24.

I have only taken four specimens of this moth in Wanganui this summer.

Ovum.

Class.—Flat.

Shape.—Oval. Micropylar end broader than its nadir, and slightly flattened. Top and bottom somewhat compressed, but their surfaces slightly convex.

Dimensions.—Length, 0·54–0·58 mm.; width, 0·42–0·40 mm.; height.

Seculpture.—Delicate. Fine reticulations form a network of five- and six and occasional seven-sided cells, though mostly regular hexagons about 0·03 mm. diameter. Sculpturing at micropylar end roughened, blurred, and indistinct.

Micropyle.—A small slightly raised circular cell in midst of rosette of seven elongated cells. Darker in colour than rest of egg. Inner reticulations of rosette very indistinct. Total diameter, about 0·04 mm.

Shell.—Strong; shiny; transparent; smooth within cells.

Colour.—Pearly white, changing in a day or two to light yellow, and later to a bright yellow. A few days before hatching it turns alight grey, which darkens to a mud-colour. The larva is now plainly seen.

Note.—Laid singly, at intervals of a day or so. Strongly attached to object. Laid from September to October. Period of incubation, eight days. The larva emerges at micropylar end.

(Described, 27th September, 1912.)

Tatosoma timora Meyr.

Totosoma agrionata Meyr., Trans. N.Z. Inst., 16, p. 68. T. timora Meyr., Trans. N.Z. Inst., 17, p. 64; Fereday, Trans. N.Z. Inst., 30, p. 340; Hudson, N.Z. Moths and Butterflies, p. 40, pl. vi, figs. 28, 29.

Very plentiful in Wanganui at times.

Ovum

Class.—Flat.

Shape.—As viewed from above, oval; micropylar end flattened, and broader than its nadir, which in some cases is also slightly flattened. Transverse section oval; top and bottom much flattened.

Dimensions.—Width, 0·49 mm. (at micropylar end); length, 0·63 mm.; height, 0·35 mm.

Sculpture.—Strong. Reticulations forming a network of irregular pentagonal and hexagonal cells about 0·02 mm. diameter.

Micropyle.—Situated in a broad, saucer-like depression about 0·22 mm. diameter. The micropyle consists of a minute circular cell within a rosette of about eight elongated cells. Diameter of rosette, about 0·08 mm. The whole is very indistinct.

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Shell.—Fairly strong; shiny; transparent; very slightly roughened within cells.

Colour.—When fresh laid, yellow. In four or five days darker orange-coloured areas appear here and there on the shell, and later a black area (the caput) appears at micropylar end. The larva can be plainly seen.

Note.—Laid singly. Strongly attached to food plant—in fact, the eggs can hardly be removed without breakage. A few days after being laid the top of the egg collapses a great deal, and the whole egg assumes a very dented appearance. Forty-three eggs obtained from one moth. Laid, 21st September; hatched, 5th October = fourteen days. The larva emerges at micropylar end.

(Described, 21st September, 1912.)

Xanthorhoe rosearia Dbld.

Cidaria rosearia Dbld., Dieff. N.Z., 2, p. 285. Epyaxa rosearia Meyr., Trans. N.Z. Inst., 16, p. 71. See also Hudson's N.Z. Moths and Butterflies, p. 57, pl. 7, figs. 22, 23; Fereday's List N.Z. Lep., Trans. N.Z. Inst., 30, p. 340 (Epyaxa rosearia).

This little moth has been rare in Wanganui this year, but is generally common, and greatly attracted by light.

Ovum. Plate II, fig. 9.

Class.—Flat.

Shape.—Longitudinal section oval; sides almost parallel. The micropylar end is greater in height than its nadir. Top and bottom are flattened, though at the micropylar end a cross-section is almost circular, and at the base oval. Micropylar end flattened.

Dimensions.—Length, 0·58 mm.; height (at micropyle) 0·37 mm., (at base) 0·26 mm.; width, 0·37 mm.

Sculpture.—Reticulations fine, forming a network of shallow hexagonal and pentagonal cells over whole surface of egg. Diameter of cells, about 0·02 mm.

Micropyle.—A small circular cell about 0·01 mm. diameter enclosed in a rosette of elongated cells. The rosette is encircled by a band of cells longer than broad, lengthened in a direction radial from the micropyle, often four-sided, though sometimes five. These cells are about 0·02 mm. long by 0·005 mm. wide.

Shell.—Strong; shiny; transparent; smooth within cells.

Colour.—Very pale cream, turning to light yellow, and later to a brilliant orange tint.

Note.—Laid singly, and well attached to the object upon which they are laid. The egg becomes somewhat dented after a week or two. Laid in June and hatched in July.

(Described, 14th June, 1912.)

Xanthorhoe cinerearia Dbld.

Cidaria (?) cinerearia Dbld., Dieff. N.Z., 2, p. 286. Larentia cinerearia Meyr., Trans. N.Z. Inst., 16, p. 83; 17, p. 64. See also Hudson's N.Z. Moths and Butterflies, p. 67, pl. 8, figs. 2, 2a; Fereday's List N.Z. Lep., Trans. N.Z. Inst., 30, p. 343 (Larentia cinerearia).

This little moth is very common at Wanganui during the early summer.

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Ovum. Plate I, fig. 5.

Class.—Flat.

Shape.—Longitudinally oval; micropylar end much broader than its nadir, and slightly flattened. Transverse section oval, top and bottom flattened, and collapse a good deal as the embryo develops.

Dimensions.—Width, 0·35–0·37 mm.; length, 0·49–0·53 mm.; height, 0·28 mm.

Sculpture.—Strong. Surface broken up into shallow hexagonal and pentagonal cells 0·02–0·03 mm. diameter.

Micropyle.—Micropylar platform flat, about 0·10 mm. Micropyle situated in the centre of a rosette of eight very finely reticulated cells, surrounded by a band of almost circular cells twelve in number and about half the size of the cells forming the sculpture of the egg. Diameter of rosette, 0·04 mm.

Shell.—Fairly strong; transparent; shiny; slightly roughened within cells.

Colour.—When fresh laid, pearly white, changing in a few days to a bright yellow. A day or so before hatching the egg turns a dirty mottled grey, and the hairs of the larva can be clearly seen.

Note.—The eggs were laid singly and in small batches of from three to five on the sides and projecting fibres of the box. Are well attached to whatever they are laid on. Thirteen, twenty-five, and thirty-one eggs were obtained from different moths. Laid in October and November. Period of incubation, about fifteen days. Larva emerges from micropylar end.

(Described, 19th November, 1912.)

Notoreas zopyra Meyr.

Pasithea zopyra Meyr., Trans. N.Z. Inst., 16, p. 89. Notoreas zopyra Meyr., ib., 18, p. 184; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 344; Hudson, N.Z. Moths and Butterflies, p. 74, pl. 8, figs. 18, 19.

This beautiful species was caught on Mount Egmont, at an elevation of about 3,000 ft. Only the one specimen was seen.

Ovum.

Class.—Flat.

Shape.—Longitudinal section oval; micropylar end slightly broader than its nadir. Transverse section oval.

Dimensions.—Length, 0·63 mm.; width, 0·47–0·44 mm.; height, 0·37 mm.

Sculpture.—Shell covered with a network of fairly regular shallow hexagonal cells, diameter 0·09 mm. Cells largest at micropylar end. Reticulations roughened.

Micropyle.—Reticulations cease within 0·05 mm. of micropyle, which consists of a green oval cell 0·03 mm. by 0·02 mm., and is raised above surrounding shell.

Shell.—Strong; transparent; slightly shiny; roughened within cells. When viewed under a high power it is seen to be covered with very minute pimples, most numerous at base of egg; even the reticulations are studded with these.

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Colour.—When fresh laid, light yellow. Infertile eggs turn yellow, and collapse.

Note.—Laid singly. Ten obtained in January. Well attached to object. (Described, 7th January, 1913.)

Selidosema suavis Butl.

Pseudocoremia suavis Butl., Cist. Ent., 2, p. 497. Pseudocoemia lupinata Meyr., Trans. N.Z. Inst., 16, p. 98. Boarmia suavis Meyr., Trans. N.Z. Inst., 23, p. 101. See Meyr., Trans. N.Z. Inst., 24, p. 216, as to Selidosema. Hudson's N.Z. Moths and Butterflies, p. 83, pl. 9, figs. 3, 4; Fereday's List N.Z. Lep., Trans. N.Z. Inst., 30, p. 345.

Very common at Wanganui throughout the early summer.

Ovum. Plate II, fig. 4.

Shape.—Both longitudinally and transversely oval. The micropylar end is slightly flattened, and is at a slight angle to the micropylar axis; it is broader than its nadir. Top and bottom much flattened. Base well rounded.

Dimensions.—Length, 0·75–0·77 mm.; width, 0·54–0·58 mm.; height, 0·47–0·49 mm.

Sculpture.—Both ends of the egg are capped as far as the shoulder with a network of deep fairly regular hexagonal and pentagonal cells. The middle portion of the egg between these caps is ribbed longitudinally with rather coarse parallel reticulations at slightly varying distances from one another. The distance betweeen the shoulders of the egg, or the length of the ribs, is 0·47 mm. This portion of the egg is also ribbed transversely by somewhat finer reticulations, which, with the main ribs, form parallel rows of quadrilateral cells, deep, and twice as long as broad, the longer side being at right angles to the micropylar axis. Viewed under a high power the longitudinal ribs are found to be wavy and not perfectly straight, thus making the cells modified hexagons. The length of these cells is about 0·05 mm., and the width about 0·02 mm. Each angular point of the cells is surmounted by a small white globular knob; these are very minute, and are most plain at the ends of the egg. Just before the hatching of the egg the reticulations become white and very plain.

Micropyle.—Situated in a rosette of six elongated cells, much roughened and very indistinct; diameter, 0·10 mm. The micropyle itself is free of the white elevations before referred to.

Colour.—When laid, dark green, which becomes darker in a few days, and large brown areas appear. The brown inclines to red. In a week or two the egg is covered with a red and brown mottling. Some days before hatching two or more broad bands of purple appear, extending the whole length of the egg. At this time the larva is plainly seen within the egg.

Note.—The eggs are very large for the size of the moth. Batches of sixty-two and eighty-six eggs were obtained inserted in the cracks of the box in irregular heaps. They were slightly attached to the box and to each other. Infertile eggs remain green, and collapse. Ova obtained in April and October, and take about three weeks to hatch. The larvae emerge through the micropylar end, and are extremely active, but do not make their first meal off the empty shell.

(Described, 22nd April, 1912.)

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Selidosema fenerata Feld.

Rhyparia fenerata Feld., Reise der Nov., pl. cxxxi, fig. 7. Zylobara fenerata Butl., Cist. Ent., 2, p. 498. Boarmia fenerata Meyr., Trans. N.Z. Inst., 20, p. 61. Zylobara fenerata Meyr., Trans. N.Z. Inst., 16, p. 97. See Meyr., Trans. N.Z. Inst., 24, p. 216, as to Selidosema. Hudson, N.Z. Moths and Butterflies, p. 82, pl. 8, figs. 50, 51; Trans. N.Z. Inst., 32, p. 11: Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 345.

This moth is rare in the Wanganui district.

Ovum.

Class.—Flat.

Shape.—As seen from above, oval; greatest diameter nearest micro-pylar end, which is flattened and not quite at right angles to the longitudinal axis. Micropylar end broader than its nadir, which is well rounded. Transverse section oval; top and bottom flattened.

Dimensions.—Length, 0·72 mm.; greatest width, 0·54 mm.; height, 0·42 mm.

Sculpture.—Strong. Surface of shell covered with deep, irregular hexagonal cells, about 0·06 mm. diameter. In some eggs the cells show a slight arrangement, being either in rows extending the whole length of the egg or in bands traversing the egg at right angles to the longitudinal axis; but in all cases such rows or bands are very irregular. Each angular point of the cells is surmounted by a minute white elevation.

Micropyle.—The shell immediately surrounding the micropyle is depressed, while the micropyle itself, situated in a rosette of elongated cells, is raised. Total diameter, 0·10 mm. Very indistinct. The small white elevations cease at the margin of the rosette.

Shell.—Shiny; strong; transparent; roughened within cells.

Colour.—Dark green. Dark-brownish areas appear in about a week.

Note.—Laid singly. They are but slightly attached to object. Laid in September, and hatch in about three weeks. The eggs get dented slightly soon after being laid.

(Described, 20th September, 1912.)

Selidosema dejectaria Walk.

Boarmia dejectaria Walk., l.c., p. 394; Butl., Cat. Lep. N.Z., p. 12, and Proc. Zool. Soc. Lond., p. 390; Meyr., Trans. N.Z. Inst., 16, p. 100., See Meyr., Trans. N.Z. Inst., 24, p. 216, as to Selidosema. Hudson, N.Z. Moths and Butterflies, p. 86, pl. 9, figs. 19–24; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 346.

This beautiful moth is common around Wanganui throughout the summer. Three varieties of it are also common.

Ovum.

Glass.—Flat.

Shape.—This egg is very much like a fowl's in shape, but the broadest end (micropylar) has not a regular curve, one side being slightly bulged. A transverse section of the egg is oval; the top and bottom surfaces are slightly flattened.

Dimensions.—Length, 0·82 mm.; height, 0·58 mm.; width, 0·68–0·70 mm.

– 86 –

Sculpture.—The entire surface of the egg is pitted with large shallow hexagonal cells, saucer-like, deepest in the centre, and about 0·01 mm. diameter. Each corner of the cells is surmounted by a white elevation. These elevations are cylindrical in shape, with a flat top; diameter, 0·01 mm.; height above reticulations, 0·01 mm. Seen under a high power these elevations seem to have a hollow passage through their centre communicating with the interior of the egg. The top of each elevation is depressed towards the centre.

Micropyle.—I have examined numbers of these eggs, but have failed to find any form of micropyle. Where the micropyle ought to have been was one of the large shallow cells with the white elevations on ita angular points, as on the rest of the shell. The question is, Is there, for a fact, a communication with the interior of the egg through the white nodules referred to, and, if so, do these nodules constitute the micropyles?

Shell.—Very strong; shiny; transparent; within the cells numbers of small wrinkles extend across the whole surface of the cell.

Colour.—When fresh laid, dull heavy green. Viewed under a medium power the floor of the cells seems to have slight cellular markings of darker green, which, as the embryo develops, turn red, giving the egg a reddish mottled appearance. A few days before hatching the green and red mottling is interrupted by large blackish-brown areas, and the larva can be distinctly seen.

Note.—Strongly attached to food plant. Laid singly. Larvae eat their way out at the micropylar end, but otherwise leave the shell untouched. Just before hatching the reticulations on the shell become white and very clear. Eggs were obtained in May, October, November, and April. Laid, 4th October; hatched, 8th November = thirty-six days: laid, 1st November: hatched, 25th November = twenty-five days. Between forty and fifty eggs seems the usual number for a moth to lay. On the 12th April I found two freshly laid eggs on the main stem of a pear-tree, about 12 ft. from the ground. They were 2 in. apart, and well cemented to the stem, and were laid on that portion of it where two or three other branches unite with the main stem. The bark of the stem was covered with a green fungoid growth, and the colour of the eggs gave them splendid protection.

(Described, 29th May, 1912.)

Declana floccosa Walk.

Declana floccosa Walk., l.c., 15, p. 1649; Meyr., Trans. N.Z. Inst., 16, p. 102; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 346; Hudson, Trans. N.Z. Inst., 32, p. 12; Hudson, N.Z. Moths and Butterflies, p. 96, pl. 10, figs. 39–47.

This pretty moth is very plentiful at Wanganui during the summer. I have come across six varieties.

Ovum. Plate I, fig. 3.

Class.—Upright.

Shape.—Transverse section circular. Longitudinal section ninepin-shaped. Micropylar end has a much greater diameter than its nadir. Micropyle slightly flattened, base well rounded. These eggs look like miniature fowl's eggs standing on their small ends.

Dimensions.—Height, 0·72 mm.; greatest diameter, 0·61 mm.; peripheral distance from micropyle to greatest diameter, 0·33 mm.

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Sculpture.—The surface of the shell is covered with very fine reticulations, forming five-, six-, and seven-sided cells (extremely shallow). At each corner of the cells the reticulations are surmounted by a small knob. These knobs are not only confined to where the reticulations intersect, but are scattered indiscriminately along the reticulations themselves, excepting immediately around the micropyle; they catch and reflect the light, and make the egg appear to be spangled with minute silvery globules.

Micropyle.—Consists of a five-armed-star shaped cell surrounded by nine elongated shallow cells in the form of a rosette of 0·06 mm. diameter; is of a darker green than rest of egg, and is slightly raised.

Shell.—Very strong; shiny; transparent; roughened within cells.

Colour.—Light green with a bluish tinge, turning in a few days to dark brown, to chocolate, and then to reddish-brown. In some eggs large areas of the original bluish colour remain on the egg till a few days before hatching, the rest of the egg being marbled in reddish-brown and chocolate. In some cases the margins of these areas are well defined, the colours remaining distinct, and not blending into each other. Just before hatching the larvae can be seen within the eggs, their highly coloured markings giving the eggs a very curious brilliantly striped appearance. Infertile eggs remain bluish, and do not go through further colour-changes.

Note.—Laid in rows in small batches, and singly. All eggs have a slight leaning out of the perpendicular, and as the larva emerges by means of a hole eaten through the micropylar end its weight forces the shell over on to its side; all empty shells are found thus, and the eggs might be mistaken for the flat class. The eggs are slightly attached to object and to each other, and when fresh laid have a very distended appearance. Batches of fortysix and thirty eggs obtained in the months of September and January respectively. Incubation takes about a month.

(Described, 12th September, 1912.)

Declana atronivea Walks.

Detunda atronivea Walk., Suppl. 2, 619. Chlenias (?) manxifera Fereday, Trans. N.Z. Inst., 12, 268, pl. ix, fig. 1. Detunda atrovinea Meyr., Trans. N.Z. Inst., 16, p. 101. Declana, atronivea Hudson, N.Z. Moths and Butterflies, p. 95, pl. 10, figs. 33, 34; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 346, as Detunda atronivea.

This beautiful moth is rare in the Wanganui district; but is very common about Mount Egmont and Ruapehu, and in the high bush country of the upper Wanganui River. It is mostly found at an elevation of about 2,000 ft.

Ovum. Plate I, fig. 11.

Class.—Flat.

Shape.—Longitudinal section oval; micropylar end slightly flattened. Transverse section oval; top and bottom flattened.

Dimensions.—Length, 1·10 mm.; width, 0·93 mm.; height, 0·72 mm.

Sculpture.—The shell is covered with small white elevations about 0·01 mm. diameter and 0·015–0·02 mm.; apart. These are joined by squat. roughened reticulations forming very shallow fairly regular hexagons. The elevations mentioned above appear to be hollow, and to communicate with the interior of the egg.

Micropyle.—Consists of a small circular cell 0·005 mm. diameter, situated, in a rosette of about twelve elongated cells. This is surrounded by a band.

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of hexagonal cells, twice as long as broad, lengthened in a direction radial from the micropyle. The dimensions of these cells are—length, about 0·02 mm.; width, 0·01 mm. Diameter of rosette is 0·05 mm. There is a second band of fairly regular hexagonal cells; diameter, 0·015 mm. These reticulations are extremely fine and minute.

Shell.—Strong; transparent; very rough; has a slight sheen.

Colour.—Dull heavy green, turning in a week to a light blue, and almost entirely covered with small circular purple spots about 0·015 mm. diameter. A few days before hatching the egg is a light mottled-purple colour, and the larva can be plainly seen.

Note.—Laid singly. Well attached to object. Larvae emerge micropylar end. Laid, 3rd January; hatched, 14th January = eleven days.

(Described, 4th January, 1913.)

Drepanodes muriferata Walk.

Gargaphia muriferata Walk., l.c., 16, p. 1635; Butl., Cat. Lep. N.Z. p. 13. Panagra ephyraria Walk., l.c., 16, p. 1761. Drepanodes muriferata Meyr., Trans. N.Z. Inst., 16, p. 107; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 347; Hudson, N.Z. Moths and Butterflies, p. 91, pl. 10, figs. 7 to 12.

Scarce in Wanganui district this year.

Ovum. Plate II, fig. 7; Plate I, fig. 2.

Class.—Flat.

Shape.—Oval. Micropylar end flattened and slightly broader than its nadir. Top and bottom much flattened.

Dimensions.—Length, 0·72 mm.; width, 0·56 mm.; height, 0·47 mm.

Sculpture.—A network of hexagonal cells covers the egg; very plain at micropylar end, but becoming more and more indistinct as it approaches the base. Cells about 0·04 mm. diameter. Very minute protuberances surmount the reticulations at the points of juncture.

Micropyle.—Situated within a rosette of about nine elongated cells; about 0·06 mm. total diameter. Very indistinct.

Shell.—Strong; transparent; somewhat shiny; roughened.

Colour.—When fresh laid, white with faint greeny-yellow tinge. In two days many of the cells on the egg turn a brilliant red. The number of these red cells increases slightly, and in some cases two or more unite. A large irregular area of red covers the micropyle. The rest of the egg now gets yellowish, and just before hatching all the red areas disappear, leaving the egg banded with broad and indistinct russet-red markings. The larva can now be distinguished.

Note.—Laid singly, sometimes in small bunches or in rows, and inserted in crannies. Well attached to object. Thirty-two eggs obtained. The shell gets slightly dented. Laid, 14th October; hatched, 2nd November = nineteen days.

(Described, 16th October, 1912.)

Mecyna blairdalis Dbld.

Mecyna blairdalis Dbld., Dieff. N.Z., 2, p. 287.

A very common species at Wanganui, and is best taken by sweeping the long grass in the fields during any part of the day.

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Ovum. Plate I, fig. 6.

Class.—Flat (?).

Shape.—Oval. Exceedingly scale-like. Top surface slightly convex.

Dimensions.—Width, 0·68 mm.; length, 0·82 mm.; perpendicular height of egg-mass, 0·16 mm.

Sculpture.—Reticulations delicate and extremely fine, but easily distinguishable, forming an irregular network of lozenge-shaped figures (cells), lengthened in a direction parallel to the longitudinal axis of the egg. Cells composed of four, five, and six sides, very irregular in shape, and about 0·04 mm. long by 0·02 mm. wide.

Micropyle.—Not distinguished.

Shell.—Frail; cannot be touched without damage; transparent; shiny varnished appearance; roughened within cells.

Colour.—When fresh laid, white with very pale cream tinge. The second day the embryo can be seen within the egg in the shape of a broad U with the arms curved spirally inwards. On the sixth day two small brown areas, about 0·14 mm. apart, appear at the upper end of the egg. During the next day or two these become black, while two other small light-brown areas appear between and slightly above the former two. The middle portion of the egg assumes a darkened yellowish tinge, and the embryo larva, although very transparent, can be seen within the egg. The first pair of brown areas that appeared were the eyes, the other pair the mandibles of the larva. Infertile eggs turn slightly yellow, and collapse.

Note.—The eggs are laid singly and in small batches. Thirty-five eggs were obtained from one moth. When laid in batches the eggs are placed in neat regular rows, each egg being about two-thirds overlapped by its neighbours. The egg-contents do not reach the outer wall of the ovum, but leave a thin, flat, transparent, slightly serrated margin. Firmly cemented to food plant and to each other, and it is quite impossible to separate them. The eggs obtained were laid on the underside of the lid of the box in which the parent was confined. Portions of this box were stained red, some parts blue, and the rest left unstained. The coloured areas were in every case carefully avoided, the eggs being laid on the lightcoloured wood. Just before hatching the reticulations on the egg become white and very plain. The larva eats its way out at the upper and uncovered portion of the egg, but does not eat the empty shell. Laid, 24th November; hatched, 7th December = thirteen days.

(Described, 24th November, 1912.).

Scoparia chimeria Meyr.

Scoparia chimeria Meyr., Trans. N.Z. Inst., 17, p. 84; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 350.

Fairly common during the early summer, and may be beaten in numbers out of the hedges.

Ovum.

Class.—Upright.

Shape.—Somewhat ninepin-shaped. As seen from above, circular; side view long and oval, base well rounded; micropylar end rounded and broader than its nadir.

Dimensions.—Height, about 0·30 mm.; diameter, about 0·47 mm.

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Sculpture.—Shell roughened, but not definitely sculptured. In some eggs there is just a slight suspicion of reticulation.

Micropyle.—Very minute. Situated in a rosette of about eight very finely reticulated elongated cells. Diameter of micropyle, about 0·005 mm.; diameter of rosette, 0·03 mm.

Shell.—Strong; transparent; slight sheen; roughened.

Colour.—When laid, white, changing in a few days to a very pale yellow tint.

Note.—Laid singly. Well attached to food plant. Laid in December. The eggs get a very dented appearance in about a week after being laid.

(Described, 7th December, 1912.)

Scoparia cyameuta Meyr.

Xeroscopa cyameuta Meyr., Trans. N.Z. Inst., 17, p. 112.

Fairly common in the Wanganui district during late summer.

Ovum.

Class.—Flat.

Shape.—Longitudinal section oval, ends somewhat pointed, the greatest width being nearer the micropylar end, which is blunter than its nadir. Transverse section oval, top and bottom flattened. Shape not constant.

Dimensions.—Length, 0·61 mm.; width, 0·40 mm.; height, 0·35 mm.

Sculpture.—Shell covered with very fine roughened reticulations, forming fairly regular shallow pentagonal and hexagonal cells about 0·02 mm. diameter. In some cases the reticulations are somewhat obliterated towards the base of the egg.

Micropyle.—Impossible to distinguish clearly owing to the very wrinkled condition of the shell at this end.

Shell.—Fairly strong; transparent; shiny; roughened within cells. Long thin wrinkles almost the whole length of the egg. The top collapses a great deal after being laid a few hours.

Colour.—Fresh laid, very light yellow. In a few days the margin of the egg changes to a light pinkish-red, and four days after the interior of the egg is taken up by a blackish wedge-shaped area, in which the hairs of the larva can be distinguished.

Note.—Fifteen eggs obtained. Laid side by side in small lots and singly. Well cemented to food plant, and cannot be detached without breakage; in some cases the eggs are slightly attached to each other. Infertile eggs turn yellowish, and collapse. Laid, 8th December; hatched, 20th December = twelve days. Larvae emerge by means of a round hole eaten in the micropylar end.

(Described, 9th December, 1912.)

Crambus flexuosellus Dbld.

Crambus flexuosellus Dbld., l.c., p. 289; Butl., Cat. Lep. N.Z., p. 18; Meyr., Trans. N.Z. Inst., 15, p. 28; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 356; Hudson, Man. N.Z. Ent., pl. 12, fig. 5.

Extremely common throughout the year. Can be taken in great numbers by beating manuka scrub.

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Ovum. Plate I, fig. 9.

Class.—Flat.

Shape.—Cylindrical; sides slightly bulged; ends flat; top and bottom slightly flattened.

Dimensions.—Length, 0·47–0·51 mm.; width, 0·28–0·35 mm.; height, 0·33–0·35 mm.

Sculpture.—Very, pronounced. There are thirteen to fifteen deep longitudinal reticulations or ribs 0·02 mm. high and 0·07–0·08 mm. apart. These are intersected by very fine transverse reticulations about 0·02 mm. apart, cutting the shell up into parallel rows of deep quadrilateral cells four times as broad as long. Under a high power these cells are really modified hexagons with strong longitudinal sides. The base is cut up into a number of deep depressions and correspondingly high irregular elevations.

Micropyle.—Micropylar end depressed. Micropyle situated in a rosette of about six elongated cells, the whole being slightly elevated. Fine reticulations radiate from the rosette to the ends of the main ribs, and are intersected by similar fine reticulations, forming shallow, very irregular cells. Diameter of micropyle, 0·02 mm.; diameter of rosette, 0·10 mm.

Shell.—Strong; transparent; shiny; roughened within reticulations.

Colour.—When laid, the egg is of a pale-cream tinge, turning in a day or two to a very light pink. The eggs recorded were laid on the 3rd November, and between this date and the 8th November, the changes took place. The egg now assumed an orange-pink colour, and on the 10th November was of an even terra-cotta. No further changes took place till the 24th, when one or two small black spots appeared at the micropylar end. On the 27th large almost black areas were seen at this end, and during the next day or so these areas turned quite black, while the rest of the egg lost much of its brilliant colouring. On the 1st October the larva emerged at the micropylar end.

Note.—Laid singly. Seventy-two eggs in all obtained from one moth. Not attached to object or to each other. Many of the eggs were dropped indiscriminately; others were inserted in crevices of the box in which the moth was kept. Period of incubation, about twenty-six to twenty-eight days.

(Described, 6th November, 1912.)

Ctenopseustris obliquana Walk.

Teras obliquana Walk., l.c., 28, p. 302; Butl, Cat. Lep. N.Z., p. 19. Paedisca obliquana Meyr., Trans. N.Z. Inst., 15, p. 60. Ctenopsuestris obliquana Meyr., Trans. N.Z. Inst., 17, p. 146; Fereday, List N.Z. Lep., Trans. N.Z. Inst., 30, p. 359.

This little moth is extremely common at Wanganui, and I have come across five varieties. Walker describes the same moth in Butler's “Catalogue of New Zealand Lepidoptera” under the names of Teras obliquana, Teras spurcatana, Sciaphila transtrigana, Sciaphila turbulentana, Teras cuneiferana, and Teras congestana.

Ovum.

Class.—Flat (?).

Shape.—Oval in outline. Exceedingly flat and scale-like. Top surface slightly convex.

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Dimensions.—Length, 0·86–0·96 mm.; width, 0·65–0·82 mm.; height of egg-mass, 0·12 mm.

Sculpture.—Reticulations exceedingly fine, and in many parts of the egg indistinguishable. A lozenge-shaped reticulation covers the shell, and is composed of four-, five-, and six-sided figures, roughly 0·08 mm. by 0·03 mm., but very irregular in size and shape; lengthened in a direction radial from the micropyle.

Micropyle.—Formed of a rosette of about twelve elongated cells surrounded by a band of other and larger elongated cells of hexagonal formation. Situated towards the upper and uncovered end of the ovum. Diameter of rosette, about 0·065 mm.; diameter of micropyle, about 0·005 mm. (some times larger).

Shell.—Flexible; strong; highly transparent; varnished appearance; slightly roughened within reticulations; gets much wrinkled as egg matures.

Colour.—When fresh laid, dull green. In a few days the green colouring seems to be all absorbed by the embryo, which can be plainly seen, leaving the rest of the egg very transparent. Two small black spots now appear at upper end of egg about 1 mm. apart, and later two small brown areas appear between and slightly above these. The head of the larva now appears, the black spots referred to being its eyes and the brown areas the mandibles. Light-yellowish areas appear within the rest of the egg, and the whole larva can be plainly seen. Infertile eggs quickly collapse and dry up.

Note.—Laid in batches of about thirty eggs. The egg-batches look as if they were composed of a glutinous substance resembling drops of gum or varnish. The eggs are laid in neat regular rows, but about two-thirds of each egg is covered by its neighbours, the ovum being so placed in relation to the egg-mass that the micropyle is outwards and not covered by other ova. Strongly cemented to food plant and to each other. As the embryo matures an oval depression appears in the upper surface of the egg. The green egg-contents do not reach the outer wall of the ovum, but leave a thin, flat, transparent, slightly serrated margin. Laid in December. Ninety, sixty-three, and forty-three eggs were obtained from different moths. Period of incubation is about eight days in favourable weather. The eggs were always laid on the blue binding of the boxes in which the moths were kept, and were extremely difficult to distinguish. I have found batches of the eggs on the upper surface of the English ivy leaves, but have never come across the larvae. In almost all such cases the eggs were attacked by parasites. The green colouring of the eggs is naturally one for protection. The larvae emerge from the upper and free end of the egg, and do not eat the egg-shell afterwards.

(Described, 8th December, 1912.)

Phloeopola confusella Walk.

Phloeopola confusella Walk.: Meyr., Proc. Linn. Soc. N.S.W., 1883, p. 354; Meyr., Trans. N.Z. Inst., 43, p. 69.

I have got two or three specimens of this pretty little moth around Wanganui. It seems to be rare elsewhere.

Ovum. Plate I, fig. 4.

Class.—Flat.

Shape.—Longitudinal section oval; micropylar end slightly broader than its nadir. Transverse section circular; micropylar end flattened, base well rounded.

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Dimensions.—Length, 0·58 mm.; height, 0·35 mm.; width, 0·35 mm.

Sculpture.—Finely ribbed longitudinally. No transverse reticulations. Ribs almost parallel, 0·05 mm. apart, about twenty-two in number. In some cases two ribs coalesce some distance from the micropylar end, and continue to the micropyle as one.

Micropyle.—Micropylar end flattened and slightly sculptured in very shallow cell formation. Micropyle consists of a small circular cell about 0·015 mm. diameter. Very indistinct.

Shell.—Very strong; slight sheen; transparent; entirely covered with extremely minute pimples when viewed with a high power. At the micropylar end these are larger, though less numerous than on rest of egg, being twice as high as broad; height, 0·015 mm.

Colour.—When fresh laid, light cream tinged with green, changing in about a week to light grey slightly tinged with purple. The purple tint becomes stronger at the micropylar end, shading off towards the base.

Note.—Very well attached to object. Laid singly and in small bunches inserted in cracks and crannies. When laid in lots they are arranged, end to end, in regular rows. Eighty-three eggs obtained. Laid, 9th January; hatched, 28th January = nineteen days. Larvae emerge from micropylar end.

(Described, 10th January, 1913.)

Alucita monospilalis Walk.

Aciptilus monospilalis Walk., l.e., 950. A. patruelis Feld., Reise Nov., pl. cxl, 56. A. monospilalis Meyr., Trans. N.Z. Inst., 17, p. 124. Pterophorus monospilalis Hudson, Trans. N.Z. Inst., 28, p. 379. Alucita monospilalis Meyr., Trans. N.Z. Inst., 45, p. 47.

This very beautiful little moth is very common in Wanganui during the summer. It is most common in November, and I have found numbers of the ova, larvae, and pupae on the English ivy during this month. The moth is again very plentiful in January, and still later in April. The larva feeds on the upper surface of the leaf, quite exposed. It is very destructive to the ivy on account of its great numbers and its voracious appetite. The full-fed larvae simply suspend themselves from a silken pad on the underside of a leaf by means of the cremastral hooks on the anal segment; no cocoon or other protection for the pupa is used.

Ovum. Plate II, fig. 8.

Class.—Flat.

Shape.—Extremely wafer-like. Longitudinal section oval; ends well rounded and equal. Transverse section oval; top and bottom flattened or quite flat.

Dimensions.—Length, 0·47–0·49 mm.; width, 0·37–0·38 mm.; height, 0·19–0·23 mm.

Sculpture.—Extremely fine; hardly discernible even under high powers. Very slight cellular structure on shell.

Micropyle.—Small deep circular cell surrounded by four or more similar but shallower cells. Very indistinct. About 0·02 mm, diameter.

Shell.—Very transparent; strong; smooth; highly glossy.

Colour.—Pearly white. Light-yellowish areas appear around the margin of the egg in about a week, and a small brown area (the caput) appears at

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micropylar end. In about four days after being laid the embryo can be seen in the shape of a broad U with the arms wound spirally inwards, but as the egg matures this disappears, giving place to light-yellowish areas. Larva plainly seen a few days before hatching.

Note.—Laid singly and in pairs; well attached to underside of leaf of food plant. A day or two after being laid the top of the egg collapses a great deal, forming a large deep oval depression. Twenty-five and fifteen eggs obtained from different moths. Laid in October and January. Period of incubation, about thirteen days. The larva emerges from the micropylar end of the egg.

(Described, 6th October, 1912.)

Index to Genera and Species.
Alucita monospilalis. Nyctemera annulata.
Asaphodes megaspilata. Orthosia immunis.
Bityla defigurata. Phloeopola confusella.
Crambus flexuocellus. Plusia chalcites.
Ctenopseustis obliquana. Porina cervinata.
Declana atronivea. — characterifera.
— floccosa. — umbraculata.
Drepanodes muriferata. Rhapsa scotosialis.
Elvia glaucata. Scoparia chimeria.
Euchoeca rubropunctaria. — cyameuta.
Mecyna blairdalis. Selidosema dejectaria.
Melanchra composita. — fenerata.
— dotata. — suavis.
— insignis Tatosoma timora.
— liganana. Venusia verriculata.
— mutans. Xanthorhoe cinerearia.
Notoreas zopyra. — rosearia.

Explanation of Plates. Plate I.

  • Fig. 1. Ovum of Melanchra dotata (as seen from above).
  • " 2. " Drepanodes muriferata.
  • " 3. " Declana floccosa (side view).
  • " 4. " Phloeopola confusella (as seen from above).
  • " 5. " Xanthorhoe cineraria.
  • " 6. " Mecyna blairdalis.
  • " 7. " Nyctemera annulata.
  • " 8. " Melanchra insignis.
  • " 9. " Crambus flexuocellus.
  • " 10. " Plusia chalcites.
  • " 11. " Declana atronivea.
  • " 12. " Rhapsa scotosialis.

Plate II.

  • Fig. 1. Ova of Melanchra mutans (batch).
  • " 2. " Melanchra composita.
  • " 3. " Asaphodes megaspilata.
  • " 4. " Selidosema suavis.
  • " 5. " Melanchra mutans.
  • " 6. " Melanchra lignana.
  • " 7. " Drepanodes muriferata (at end of first week).
  • " 8. " Alucita monospilalis.
  • " 9. " Xanthorhoe rosearia.
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Ova of Lepidoptera. XLVI.

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Ova of Lepidoptera

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Addenda.

Melanchra mutans.

When studying the eggs of this moth I was struck by the dissimilarity of the eggs in some of the batches. This led me to examine the parent moths more closely, and, although they were almost similar to the type specimen, there were slight differences in the size, colouring, and clearness of the markings, and these, combined with the dissimilarities in the eggs, caused me to class the parent moths as two distinct varieties. I examined batches of eggs of eight specimens of variety A, and in all these both the parent moths and individual eggs of different batches were startlingly alike. Of variety B, I only had the good fortune to examine batches from three moths, and the dissimilarities of these and their eggs when compared with the others, and their similarity to one another, led me to class these as another variety.

Variety A.

This moth has a slightly greater wing-expansion than the type specimen. The colouring is brown and grey. The markings, although of the same form as in the type specimen, are much more distinct.

Variety B.

The colour of this moth is a rich reddish-brown. As in variety A, the wing-expansion is slightly greater than in the type specimen, but is not so great as in variety A. The markings are white with black margins, and are beautifully distinct.