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Volume 52, 1920
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Part I.—The Genus Parectopa (Lepidoptera).

This part comprises the life-histories of—(1)Parectopa citharoda Meyr., (2) P. zorionella Hudson, (3) P. panacitorsens n. sp., (4) P. panaci-vermiforma n. sp., (5) P. panacicorticis n. sp., (6) P. panacifinens n. sp., (7) P. aellomacha Meyr., (8) P. panacivagans n. sp.

Of the remainder of the genus, P. aethalota Meyr. (Trans. N.Z. Inst., vol. 21, 1889, p. 185), P. leucocyma Meyr. (Trans. N.Z. Inst., vol. 21, 1889, p. 184), and P. miniella Feld. (see Trans. N.Z. Inst., vol. 21, 1889, p. 185) have not yet been observed. These complete the genus in New Zealand as at present known.

Those studied are all miners of the long-gallery type, and all except P. citharoda make their cocoon and pupate in the terminal part of the mine. P. citharoda offers other interesting details distinct from the rest of the genus. At present the only ova found and described belong to P. citharoda. Owing to lack of time and material I have had to omit the descriptions of the larvae of this genus, but a complete account will be given later in a supplementary part, which it is hoped will also include the species not given in the present paper. From what little I have seen of the larvae, there will be some extremely interesting points to bring to light. In my early paper onP. citharoda I gave a short sketch of the setal plan, but in light of more recent work this needs revision, and Fracker's nomenclature (” The Classification of Lepidopterous Larvae.” Illinois Biological Monographs, vol. 2, No. 1, 1915) should be adopted. The head-capsule and head-setae need investigation.

The Chief Characteristics of the Parectopa Pupa.

In shape long and slender, more or less bluntly rounded at the head (except for the pointed cephalic plate), and gradually attenuated towards the other extremity. Length averaging from 5 mm. to 8 mm. Attached to the front in its uppermost part is a heavily chitinized cutting-plate (the cephalic plate) directed upwards and forwards; on either side of this, and about midway between it and the base of the antenna, is usually a short stout incurved cornu; while in front of the cephalic plate is a pair of prominent tubercles bearing each a long slender seta. The antennae cover a portion of the outer lateral part of the pigmented eye, and extend usually the whole length of the body; they are segmented and free in their lower part. Mandibles are present, one on either side of the labrum, but are small. The maxillary palpi are very distinct in P. citharoda, adjoining the margin of the antennae externally and occupying the lower border of the eye, between it and the first legs and maxillae; in the other species, however, they are obscure and doubtful. The labial palpi are long and slender, and about one-sixth of the body-length The maxillae are long and slender, and usually reach to about midway between the ends of the first and second legs; usually a portion of the lateral margin of the upper fifth of the maxilla is encroached upon by the femur of the first leg. The third legs appear from below the second, and extend generally as far as the seventh abdominal segment. Forewings long and narrow, with pointed incurved extremities, and occupying about one-half the body-length. The ventral appendages, with the exception of the wing-tips, third legs, and antennae at their caudal extremities, are not free. The prothorax is much narrower in the mid-dorsal region than laterally. Mesothorax is the longest segment of the body, and is extended caudally. Metathorax about as long as the abdominal segments, and the wings occupy a narrow strip

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Fig.1.—Parectopa citharoda
Fig. 2.—P. zorionella.
Fig. 3.—P. panacitorsens.
Fig. 4.—P. panacivermiforma
Fig. 5.—P panacicorticis.
Fig. 6.—P. panacifinens
Fig. 7.—P. panacitorsens (North Island variety)
Fig. 8.—P. aellomacha
Fig. 9.—P. panacivermiforma (South Island form)
Fig. 10.—P. panacivagans.
(All magnified about 5 diameters.)

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as far as the second segment. Abdominal segments of about equal length, except for the terminal three; dorsum thickly covered with very fine spines movement can take place between 4–5, 5–6, 6–7; spiracles small, circular, slightly elevated, covered by the wings in the first abdominal segment, obsolete in the eighth, absent in the ninth and tenth. Cremaster absent, the terminal segment being bluntly rounded or produced into two finger-like processes, each bearing a minute apical hook. Setae present, slender; a dorsal pair on meso- and meta-thorax and abdominal segments except the last; a dorso-lateral pair and a lateral pair on most of the abdominal segments, details of which are given under the different species.

The pupa is extruded from the cocoon as far as about the first legs, and always with its dorsal surface next the surface of the leaf on or in which the cocoon is constructed. The appendages are therefore outermost. As soon as the imago has become freed it retreats to the underside of the leaf, where it shelters quietly while the wings expand and dry.

Meyrick ("Revision of the New Zealand Tineina,” Trans. N.Z. Inst., vol. 47, 1915 p. 227) gives the chief characteristics of the Gracilariadae as: “Head with appressed scales. Antennae 1 or over 1. Labial palpi slender, ascending, tolerably pointed. Maxillary palpi moderate, filiform, porrected. Forewings with 7 and 8 stalked or separate. Hindwings lanceolate or linear,” And he then divides the three genera as follows:—

Middle tibiae not thickened:—

(a.) Posterior tibiae with bristly projecting scales above: Acrocercops.

(b.) Posterior tibae without bristly scales: Parectopa.

Middle tibiae thickened with dense scales; posterior tibiae without bristly scales: Gracilaria.

Hence the absence of the thickening of scales on the middle and posterior tibiae is the distinguishing characteristic of Parectopa.

(1.) Parectopa citharoda Meyr. (The Wattle Parectopa). (Plate XXX, fig. 1.)

Parectopa citharoda Meyr., Trans. N.Z. Inst., vol. 48, 1916, p. 418; Watt, loc. cit., pp. 407–13.

For the sake of completeness I recapitulate below the chief points from my earlier paper on this species, together with a little new material that I have noted since publishing the paper referred to.

Meyrick's Original Description.

“♀. 10 mm. Head probably white (injured). Palpi white. Thorax white, patagia dark fuscous. Abdomen dark grey, sides obliquely striped with white, ventral surface white. Forewings very narrow, moderately pointed; dark bronzy-fuscous, towards apex lighter and more bronzy; five slender white blackish-edged streaks from costa, first three very oblique, first from ¼, reaching half across wing, second from middle, reaching more than half across wing, its apex closely followed by a short fine dash, third shorter, fourth fine, direct, reaching termen, dilated on costa, fifth just before apex, fine, inwardly oblique, cutting through a small round blackish spot; a white dorsal streak from base to middle, terminated by an oblique projecting streak reaching nearly half across wing; a white triangular spot on dorsum beneath apex of second costal streak; a short outwardly-oblique white streak from tornus: cilia greyish, with white bars on costal markings, and dark-fuscous median and apical lines above apex separated with whitish. Hindwings dark slaty-grey: cilia fuscous.”

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In all perfect specimens the head is white.

This pretty little moth may be found basking in the sun on the leaves of its food-plant, or flying about the shrub. Few were seen to fly far from the bush even when beaten out. It is not very shy, and can be knocked straight into the killing-bottle without using the net. Its attitude of rest is peculiar, the body being held at an acute angle to the surface of the leaf, with the head lowermost, almost touching the leaf; the hind legs are kept close to the body, and elevate the hinder part in the air, while the first and second legs are held almost at right angles to the body, close together, and slightly forwards. The Panax moths rest with the head end elevated. There are several broods during the summer, larvae being found at any time between the months from July to March. Most possibly the larva hibernates in the cocoon.

Distribution.

Wanganui. During the last few years this moth has become very plentiful wherever its food-plants happen to be growing. In December of 1919 the young leaves of the wattles in the Virginia Lake Reserve were badly infected. I also came across new and old mines in the Botanical Gardens in Wellington in September.

Food-plants.

The Australian broad- and narrow-leaved wattles (Acacia pycnantha, Acacia saligna). Indigenous food-plants still unknown. It would seem as though this moth had been introduced from Australia.

Egg-laying.

The eggs are laid on either side of the young tender leaves in no specially favoured part. They are also to be found on the young stems and seed-pods. The egg is flat, water-like, slightly rounded above, with a narrow irregular margin or rim round the circumference. Average dimensions 0.65 mm. by 0.45 mm. No marked sculpture except very minute white elevations arranged in a somewhat hexagonal pattern. Shiny; colour a pale transparent white; strongly cemented to the leaf; period of incubation about fourteen days.

The Mine.

The mine may be on either side of the leaf; is a long, narrow, slightly expanding gallery, more or less tortuous in direction, and generally up and down the long axis of the leaf. Total length from 7 in. to 8 in. Colour of early part of mine white, with a thin brown or black central line of frass;

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Fig. 1.—Mine of P. citharoda in Acacia saligna. (Natural size.)

later a somewhat lighter green than the rest of the leaf-surface; this portion of the mine loosely packed with fine frass granules. The cuticle over old mines rapidly dies and becomes brown. Badly infected leaves wither and fall from the tree. The final inch or so of the mine is often expanded into a somewhat irregular, narrow, elongated blotch.

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The Larva.

In the first stadium the minute larva is light green in colour, head light brown; it bears no setae. These do not appear till the third and last stadium, in which the general colour is light greenish-yellow with a faint white spiracular line. Length 6–7 mm.; spiracles minute, circular; prolegs on segments 3, 4, and 5, each armed with a single short transverse bar of about seven hooklets. Body covered with minute hairs. Revised details of the chaetotaxy will be given in a future paper, together with details of the head-sclerites, &c., when a comparison of all the Parectopa larvae will be given. Number of larval stadiums three, the first and second about ten days each, the third about twenty days. When full-grown the larva leaves the mine and descends to the vegetation round the foot of the tree, amongst the dry fallen leaves of which it constructs its cocoon.

The Cocoon.

This is an extremely pretty little structure of white silk; usually constructed in some concavity; its upper and outer surface slightly rounded, and covered with minute white fleecy globules, the majority of which may be removed by blowing upon them. These globules are excreted by the larva during the construction of the cocoon, and are ejected from the interior through rents torn in the covering of the cocoon by the larva itself, eighty to a hundred or more being so ejected. The construction of the cocoon occupies about two days.

The Pupa.

Colour white, to light yellow, to black with obscure white markings (see description of a typical Parectopa pupa above). The following are the chief characteristics: Head bluntly rounded; cephalic plate small, having a comparatively broad, transverse, semicircular, serrated cutting-edge; the plate is quadrilateral, being continued dorsally, and is depressed just behind the cutting-edge; the antennae extend some distance past the terminal abdominal segments; clypeus somewhat prominent, and bears a small tubercle and seta on either side just above the labrum; no lateral cornua or frontal tubercles; maxillary palpi quite distinct, fairly broad, sculptured with fine transverse rugae; labrum and mandibles a little distance above the lower margin of the eyes; maxillae narrow in their entire length, and about one-fifth of the body-length; first legs extend beyond the termination of the maxillae and meet in the mid-line, about one-quarter the body-length, their femora occupying a long narrow strip along the outer lateral margin of the maxillae; second and third legs as in type; prothorax quadrilateral, occupying a narrow strip between the antennae, only slightly narrower in the mid-dorsal region; setae present but extremely minute, only the dorsal pair being present in the meso- and meta-thorax and first abdominal segment; in segments 2 to 6 inclusive the same three pairs of setae as in type; in segment 7 the dorsal pair only, and no setae were discovered in segments 8, 9, and 10; no cremaster, terminal segment bluntly rounded and bare; movement takes place between 4–5, 5–6, 6–7, but the pupa is not active; no sign of any lateral flanges on the abdominal segments; average length of pupa 4–5 mm. A table of the chief measurements was given in the earlier paper, which the above notes are not intended to replace. Duration of the pupal stage, eleven days to a month or longer, according to climatic conditions.

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Dehiscence.

The front, with its cephalic plate, clypeus, labrum, eyes labial palpi, and maxillae, becomes separated in one piece, but remains attacked at the lower extremity of the maxillae by loose slips. There is a slight splitting along the dorsal margin of the antennae, but no violent rupture takes place, and the antennae and first and second legs retain their connection and position in one piece on either side. The vetex remains attached to the prothorax, but is cleft down its vertical suture; this cleft, continuing and dividing the prothorax, extends about half-way down the mid-dorsal region of the mesothoiax.

(2.) Parectopa zorionella Hudson (The Coprosma Parectapa). (Plate XXX, fig. 2.)

Parectopa zorionella Hudson, Ent. Mo. Mag., 3rd ser., vol. 4, p. 62, 1918.

The Imago.

Since Mr. Hudson's description of this little moth is not readily accessible to all entomologists in New Zealand, I take the liberty to reprint it here: “The expansion of the wings is ⅜ in. The forewings are elongateoblong with the costa strongly arched; very dark brownish black with very vivid steely-blue reflections; there is a large semicircular silvery-white spot on the costa a little beyond the middle; an oblique silvery-white bar beyond ¾, and two much smaller bars just before the apex; there are three minute silvery spots on the dorsum. The hindwings are dull steely-grey. The cilia of the forewings are black; of the hindwings dark grey tinged with bronze towards the body.”

The adult moth is not by any means common in the field, possibly owing to the widespread destruction of the larvae and pupae by hymen-opterous parasites; the great majority of mines that I have examined were so infested. Mr. Hudson says the imago may be found among light scrub in November. I myself have not seen the moth outside my breeding-dishes. As soon as it has emerged from the cocoon it retreats to the shelter of the underside of the leaf, where it rests in its peculiar attitude of head elevated, while its wings spread and dry.

Distribution.

The mines of this moth are common on Mount Egmont to an altitude of nearly 4,000 ft. I have found them there during the last three years, and take the following extracts from my notebook: “10/1/17, only old vacated mines found; 22/4/17, old mines, fresh mines, and larvae plentiful, no pupae; 23/12/17, mines and pupae.” Of those obtained 22/4/17 the imagos emerged about the middle of August following. Mr. Hudson records the perfect insect in November in the Botanical Gardens, Wellington, where I have found the mines quite plentiful in February, but chiefly parasited. I was in Wellington again in June and found many mines, but all empty; in September I found no mines; in December a number of pupae were obtained, and from these the imagos emerged about the end of the same month. Pupae obtained on Egmont in the beginning of January all emerged during the month. A few mines have been found in Wanganui, but so far none in the South Island. I am able to note that since the preparation of this paper Mr. George Howes found pupae at Waitomo about the end of March, 1920. It would appear as though there were two, if not three, broods in the year.

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Food-plants.

Coprosma grandifolia (kanono, raurakau), C. tenuifolia (karamu), C. lucida (karamu), C. robusta (karamu), C. retusa (taupata).

It was chiefly in the young plants of these shrubs that the mines were found, and within a foot or so of the ground. No doubt other species of Coprosma are also attacked.

Egg-laying.

The ovum has not yet been observed. It is laid, however, invariably on the under-surface-of the leaf, and as a rule near the midrib, and in the lower (basal) half of the leaf. Laid singly, and rarely more than two on any one leaf.

The Mine.

The larva mines directly into the leaf through the bottom of the egg. The mine is at first a long, slender, slightly tortuous, gradually widening gallery; the first centimetre or so being on the under-surface of the leaf, close against the cuticle, showing up white and silvery by reflected

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Fig. 2.—Mine of P. zorionella in Coprosma. (Two-thirds natural size.) (×—×, point where the mine leaves the under-surface of the leaf and comes close under the upper cuticle.

light. The remainder of the mine, however, is on the upper surface. In the last stage the gallery expands, more or less abruptly, into a large irregular blotch. The gallery at first is about 0.5 mm. in width, its

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Fig. 3.—Trace of mine of P. zorionella in Coprosma. (Two-thirds natural size.) (×—×, point where mine changed from lower to upper portion of the leaf.)

margins regular; on the upper surface of the leaf, however, the margins become irregular and slightly serrated, the margin of the blotch being very irregular as a rule, but the dentations are comparatively large and rounded. The gallery may attain a length of from 4 in. to 6 in., according to the

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limits of the leaf in which, it is contained; in small leaves it becomes incorporated in and obliterated by the blotch—so much so that no sign of any gallery can be found. It usually follows the midrib or margin of the leaf along its greater extent, sometimes being deflected by the coarser veins; in this manner its course may be slightly tortuous, but rarely markedly so. The midrib forms an impassable barrier except at its upper end. The irregular blotch may cover an expanse of about 1½ square inches. Colour of the mine conspicuously white or light green, sometimes discoloured a bright reddish-brown, but patchy in character. That part of the leaf covering the blotch is, in fleshy leaves, more or less mottled in shades of green according to the closeness of the mine to the outer cuticle. Frass exceedingly scanty, black, finely granular, occupies a thin line near one side of the gallery, sometimes abruptly changing from one side to the other. After the first moult the granules are irregularly scattered over the floor of the mine. Leaves are seldom found containing more than two mines. The blotch is almost invariably bounded on the outside by the margin of the leaf.

The Larva.

The first moult occurs about 6 cm. or 7 cm. from the commencement of the gallery. Structural details of the larva are reserved for a future paper.

The Cocoon.

The cocoon is a delicate structure of white silk within the blotch part of the mine. It is oval in outline, and compressed above and below. Average size 10 mm. by 4 mm. The head end may be slightly broader than the other. It is not conspicuous from the exterior, a very slight puckering of the leaf around its circumference, and a small degree of fullness in that part, alone betraying its presence. On holding the leaf up against the light the pupa may be distinguished by its shadow, and its health determined by the vigour of its movements when so disturbed. There is no evidence on the exterior of any prepared place for exit.

The Pupa.

As seen from the side the pupal outline is rounded at the head (except for the cephalic plate), and more prominent dorsally, There is a slight stricture in the dorsal outline at the prothorax, otherwise the dorsal outline is almost straight. Ventrally there is a fairly deep stricture between the eye and the first leg, occupied by the maxillae. Ventral profile somewhat rounded, the body becoming slightly attenuated towards the caudal extremity. A ventral view of the pupa shows the cephalic plate occupying about one-third of the width of the head between the antennae; the outline from its base to the antenna is almost straight; the greater diameter is opposite the caudal extremity of the labial palpi, the body from here becoming gradually attenuated caudally.

The head: Cephalic plate well developed into a long, slender spear-point, about one and a half times the length of the eye, twice as long as its ventro-dorsal diameter at its base, projected forward at an angle of about 45° to the long axis of the pupa; the pair of frontal tubercles bear long and slender setae, slightly longer than the cephalic plate; no trace of lateral cornua. Eyes large, prominent, only slightly covered by base of antenna. Labrum situated between eyes at about their middle, Mandibles small but encroaching caudally upon the labrum. Labial palpi

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long and slender, slightly expanded in their middle third. Maxillae broad above, narrowed between first legs, but slightly expanded at their tips, which are situated about midway between first and second legs.

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Fig. 4.—Pupa of P. zorionella, ventral view.
Fig. 5.—Lateral view of head.
Fig. 6.—Dorsal view.
cp, cephalic plate; A, antenna; F, front; LP, labial palpi; Max, maxillae; L1 L2, L3, first, second, and third legs; W1, forewing; V, vertex; E, eye; P, prothorax; mp, maxillary palp; M3, mesothorax; Mt, metathorax; W2, hindwing. (All figures of pupae are carefully drawn to scale, but all are not necessarily to the same scale.)

Maxillary palpi obscure. Antennae segmented, parallel in their lower three-fifths, but separated by the second and third legs, extended whole length of body.

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Thoracic appendages: Legs as described in type; first legs about twice as long as labial palpi: second legs constricted in their middle one-third by the first legs and maxillae; about one-third as long again as the first, and terminate just above tips of forewings; second legs terminate just below the junction of segments 6 and 7, about half-way between the ends of second legs and antennae. Forewings reaching about the middle of the fifth segment, pointed, and slightly incurved. Prothorax constricted mid-dorsally. Mesothorax as in type. Metathorax as in type, wings not extending beyond first segment. Abdominal segments, spiracles, and setae as in type, also the thoracic setae. The first abdominal segment bears only the dorsal pair of setae. All the setae are directed caudally. There is a slight lateral ridge on segments 2–8 inclusive. The dorso-lateral seta is situated just dorsal to the ridge, below the level of the spiracle, is shorter than the lateral seta, which is situated close against the dorsal margin of the wing in segments 2–5, and caudal to the spiracle. On segments 5–8 inclusive there is a second rather more prominent lateral ridge, ventro-lateral and parallel to the other; the lateral seta and spiracle are situated between these two ridges.

The pupa is very active if disturbed, twirling its abdomen in great haste; movement occurring between segments 4–5, 5–6, 6–7. Segment 9 bears only the dorsal pair of setae, while 10 bears no setae at all, but has a short pair of fleshy tubercles ventrally, each armed with a minute hook; there is a pair of minute tubercles dorsally, while caudally the segment is prolonged into two fairly stout finger-like protuberances, each armed with a minute hook at the tip.

Colour of pupa before dehisence: Head black, eyes dark red, ventral appendages black with white markings, mesothorax black, metathorax and abdominal segments light grey.

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

Chief Measurements of Pupa.
Measurement at Length from Tip of Cephalic Plate. Transverse Diameter. Ventro-dorsal Diameter.
Mm. Mm. Mm.
Base of eyes 0.88 0.82 0.71
End of labial palpi 1.65 1.00 0.88
End of first legs 2.59 0.94 0.94
End of maxillae 3.00 0.94 0.94
End of second legs 3.76 0.82 0.88
End of forewings 4.00 0.76 0.82
End of third legs 4.76 0.58 0.59
End of antennae 5.88 0.28 0.29
Extreme length 5.88

Dehiscence.

The pupa is extruded through the upper cuticle of the leaf as far as the third or fourth abdominal segment. The legs become separated in one piece on either side, but remain attached at their lower extremites by small slips. The front, with cephalic plate, eyes, labial palpi, maxillae, and antennae, remains in one piece, but is not lost. Dorsally there is a rupture across the epicranial suture, thus freeing the front and its appendages, and down the mid-dorsal arm of this suture, extending through the prothorax and upper two-thirds of the mesothorax.

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(3.) Parectopa panacitorsens n. sp. (The Panax Underside Moth). (Plate XXX, fig. 3.)

The Imago.

9 mm. Head and thorax white; antennae grey-whitish; palpi white with indistinct ring of black at apex of second joint, and a distinct subapical ring of black on terminal joint; abdomen grey-whitish; legs white, ringed with black, posterior tibiae white. Forewings light fuscous, markings white, interrupted with ochreous; a narrow dark-ochreous streak along costa at base to ⅙, a small indistinct white area at ⅙, a slightly larger and more distinct one at ⅓, a square white patch at ½, a narrow outwardly-oblique white streak at ⅔ reaching nearly two-thirds across wing, a small transverse white bar near apex, a broad white streak along dorsum from base to ⅔, interrupted at ¼ and by an outwardly-oblique wedge-shaped spot of ochreous, that at ¼ being very dark; cilia dark grey with two black lines. Hindwings and cilia dark grey.

There is also a North Island variety, which attacks Nothopanax Sinclairii. (Plate XXX, fig. 7.)

8 mm. Head light grey-whitish; palpi white with two black rings; antennae grey-whitish. Thorax grey-white with narrow central streak of fuscous dividing caudally into a small V-marking. Abdomen dark grey; legs white with black rings. Forewings golden brown irrorated with black; markings white, tending to be indistinct; cilia light brown with a distinct black line, blackish externally. Hindwings dark grey; cilia dark grey on costa, lighter bronze-grey on dorsum.

Distribution.

Several mines were found at Aberfeldy, in the Wanganui district, in May of 1918, but all were old. Several mines with pupae were obtained in the Bush Reserve, Flagstaff, Dunedin, early in November, 1919, and these emerged during the first week of December.

The North Island variety is a fairly common little moth in season on Mount Egmont at 3,000 ft. Numbers of mines were found in the vicinity of the North Egmont House and Dawson's Falls, and beside the track on the way up the mountain. Pupa were obtained fairly plentifully in December and early January, and these emerged during January and February. First found in December, 1916. No larvae or fresh mines were found during a short trip taken to the mountain in April of 1917.

Food-plant.

Nothopanax arboreum (whauwhaupaku).

The North Island variety was found only in very young plants of Nothopanax Sinclairii, generally within a foot or so of the ground.

The Mine.

The egg is laid on the under-surface of the leaf, but otherwise in no more favoured position. The mine is entirely on the under-surface of the leaf; no signs whatever of it on the upper surface. Throughout its whole. course it is a simple gallery, and very tortuous in its direction. Commencing with a width of a little under 1 mm., it has a width of 3–4 mm. in its later parts. The chief direction is in the long axis of the leaf, and the outer portions of the leaf are more mined than the centre—in fact, nearly three-quarters of the entire margin of the leaf forms the external margin of the

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mine. The gallery twists and turns, and in its course follows so close against the earlier portions that the partition between them is broken down, and finally the entire mine appears to form a huge blotch occupying about one half the leaf-surface. Though thus closely following its former track, it rarely crosses it except under direct need. The midrib forms a barrier, except in its upper and thinner part, where it is invariably crossed. The final length of the mine may average as much as 26 in. Colour in the early stages white with a fine brown central line occupied by the frass;

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Fig. 7.—Mine of P. panactitorsens in a leaf of Nothopanax arboreum. The dotted line shows the course taken by the larva; the heavily dotted line is the earliest part of the mine. (Two-thirds natural size.)

the remainder of the mine, however, is only a shade paler green than the rest of the leaf, and so is most inconspicuous. The track can be made out by the fine black frass granules strewn in close convex lines across the gallery; these are quite plain on the under-surface of the leaf if looked for, thus demonstrating the extreme thinness of the covering cuticle. There is a narrow portion of the gallery on either side not occupied by frass, so this outer margin is somewhat lighter in colour. The margins of the gallery are regular and even.

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Fig. 8.—Part of track of P. panacitorsens on underside of leaf of Nothopanax Sinclairii.
Fig. 9.—The same leaf showing part of mine visible on upper surface. (Natural size.)

In the case of Nothopanax Sinclairii the whole leaf is so mined that the entire under-cuticle can be lifted off. The mine is not conspicuous, but a trained eye can detect the paler colour of the under-cuticle, its

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freedom from attachment to the surface of the leaf, and faint frass lines. The only evidence on the upper surface of the leaf is an unusual crinkled appearance, and sometimes short lengths of the later stages of the mine where the larva has eaten deeper into the substance of the leaf and reached the upper cuticle; the pale-green portion of the mine so exposed is readily noticed. Frass is finely granular, very scanty, and offers no characteristic features. Very rarely, and then only in the larger leaves, were two larvae found working in the same leaf.

The Cocoon.

The cocoon is constructed within the terminal part of the gallery, and invariably close against the outer margin of the leaf, and usually on that side opposite the one in which the mine commenced. Shape ovoid, slightly broader at head end, 7 mm. by 3 mm.; its long axis parallel to the leaf-margin. It consists only of a very thin covering of white silk. Its presence is quite conspicuous, due to the infolding and puckering-up of the leaf round about it, and the small area of white transparent cuticle at the head end prepared for the pupal dehiscence. The pupa thrusts the fore part of its body through this window (which is, of course, on the under-surface of the leaf) at dehiscence.

In the North Island variety the cocoon is a small, flattened, oval structure of white silk within the mine, generally found near the base of the leaf. It can best be detected by holding the leaf up against the light, when the pupa may be seen within. Externally its presence may be detected on the upper surface by a slightly elevated portion of the leaf. Size, 6 mm. by 2.5 mm. There appears to be no prepared outlet for the pupa.

The Pupa.

The head as seen from the side is somewhat pointed, but rounded as seen ventrally, with a slight incision at base of antennae. Cephalic plate long and slender, three-bladed, sharply pointed, twice, as long as broad

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Fig. 10.—Ventral view of head of pupa of P. panacitorsens. Fig. 11.—Lateral view.

at its base, slightly longer than length of eye. Lateral cornua well developed, incurved, in length about three-quarters that of the plate. Frontal tubercules and setae long and slender, situated just caudally to the base of the cephalic plate; bottom of labrum about the same level as base of

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eyes; maxillary palpi obscure. Head, thoracic, and abdominal appendages as in type. Only a very narrow slip of the first femur is seen between the maxillae and first legs. Antennae slightly longer than body. There is a small dorso-lateral ridge on all abdominal segments. The meso- and meta-thoracic dorsal setae are long and slender, and directed upwards and outwards; only the dorsal setae found on segments 1 and 2; they exist on all the other abdominal segments except the last, and are directed caudally; the dorso-lateral setae in segments 3, 4, and 5 are characteristic, being extremely long and slender, those on segment 3 being the longest and as long as the width of the body at this part; they are all mounted on prominent tubercules at the cephalic end of the lateral ridges, and project upwards and outwards. The dorso-lateral setae on segments 6, 7, and 8 have a similar position, but are small and directed caudally; there is a minute lateral seta ventral to and below the spiracle close against the outer or dorsal margins of the wing, and is found in segments 3–7 inclusive. All other particulars as in type. Tenth abdominal segment bi-digitate.

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Chief Measurements of Pupa.
Measurement at length from Tip of Cephalic Plate. Transverse Diameter. Ventro-dorsal Diameter.
Mm. Mm. Mm.
Base of eyes 0.76 0.76 0.55
End of labial palpi 1.55 0.83 0.79
End of first legs 2.48 0.72 0.79
End of maxillae 3.10 0.62 0.76
End of second legs 3.38 0.55 0.72
End of forewings 3.79 0.45 0.62
End of third legs 4.62 0.24 0.27
End of tenth segment 5.10
End of antennae 5.38

Dehiscence.

A transverse split along the epicranial suture frees the frontal head piece, with its cephalic plate, antennae, labial palpi, and maxillae, all in one piece, and this is forced forward, but retained in its lower extremity by loose ships; the first and second legs form a separate piece on either side, but are retained more or less in position; a mid-dorsal splitting cleaves the vertex, prothorax, and upper two-thirds of the mesothorax.

(4.) Parectopa panacivermiforma n. sp. (The Panax Vermiform Moth). (Plate XXX, figs. 4 and 9.)

The Imago.

10 mm. Head white; palpi white, with a few black scales on outer side of apex of second joint and a distinct black subapical ring on terminal joint; antennae grey-whitish. Thorax white, with a narrow central line of light fuscous branching caudally into a small V-shaped marking around metathorax; legs white with black rings. Abdomen grey-whitish. Forewings light bronze-brown, suffusely irrorated with black; markings white; base of wing to about ¼ white with a fine streak of dark fuscous along costa, and a small outwardly-oblique spot of dark fuscous about the middle; three short outwardly-oblique white markings on costa in middle ⅓, the

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outermost being the smallest, the interspaces densely irrorated with black; three rather obscure lines of white in outer ⅓; cilia whitish with distinct band of black internally and a second indistinct one externally; a small triangular spot of white on dorsum at about ½; two rather less distinct white spots at ¾. Hindwings dark-grey; cilia grey on costa, grey with bronzy reflections on dorsum.

Distribution.

Found plentifully on Mount Egmont in the vicinity of North Egmont House and Dawson's Falls (3,000 ft.). Many larvae were found here in April of 1917. The pupae may be obtained about the end of December, and emerge during January and February. Also found at Dunedin, on Flagstaff Hill, chiefly around the margin of the bush. The pupae are to be obtained in November; larvae are plentiful in the early part of the month. The first images emerged on the 16th December.

Food-plant.
Nothopanax Sinclairii; Nothopanax simplex (haumakoroa), in South Island.
Egg-laying.

The egg itself has not yet been found, but the following few particulars have been gleaned from observations on young mines. The eggs are laid singly, rarely more than one or two on any one leaf, upon the upper surface, and near but rarely touching the midrib, and generally in the lower part of the leaf towards the stem.

The Mine.

The mine is a very characteristic one. It is a simple gallery throughout, and vermiform in character, the loops being very closely applied to one another, never anastomosing or crossing. As a rule the gallery at first

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Figs. 12, 13.—Mines of P. panacivermiforma in Nothopanax Sinclairii. (Natural size.)

winds backwards and forwards in slightly increasing distances, closely applied to itself, and in a direction more or less parallel to the long axis of the leaf; then with an almost remarkable abruptness it changes its

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direction for one almost at right angles to the earlier one, now crossing the leaf in curved sweeps from edge to midrib, this latter forming a certain obstacle to trespass on the other half of the leaf. The spot where the general change of direction takes place no doubt marks the situation where the larva underwent its first moult. On reaching the upper region of the leaf the mine becomes less vermiform in character and becomes rather tortuous in its direction, crossing the midrib in its upper and thinner part, and continuing down the other half of the leaf in more or less close proximity to the midrib or outer margin. This latter portion of the mine is often deeper in the leaf than the earlier vermiform part, and consequently is more difficult to detect. In this final part the width of the gallery is about 3/32 in. The entire mine is in the upper surface of the leaf, and no trace of it can be seen beneath. Colour of mine a paler green than other portions of the leaf, but even so the mine is not a very conspicuous object at a little distance. The terminal portion of the gallery may be slightly enlarged, and within it the cocoon is constructed, a small area of the upper cuticle of the leaf at the extreme end of the mine being first prepared to a transparent thinness for the exit of the pupa later. The frass is finely granular, pale in colour, not very abundant, and occupies a rather broad band in the central third of the gallery.

The South Island type differs from the above. In the earlier part the mine is a simple vermiform gallery very similar to that of P. panaxvermiformella both in size and character; later, however, instead of ending in a somewhat tortuous and widened gallery, it expands into a

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Figs. 14, 15.—Mines of P. panacivermiforma (South Island) in leaves of Nothopanax simplex. (Natural size.)

relatively large blotch, which may occupy the entire leaf in small ones, or all or the greater part of one half of the leaf in larger ones. The entire mine is on the upper surface of the leaf, and is pale green in colour, and not very conspicuous at a distance The final blotch may occupy about

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1 square inch; it is generally more closely applied to the outer margin of the leaf, where there is plenty of room. The midrib forms a barrier in its basal two-thirds. The blotch is irregular in shape, but all irregularities are rounded. Frass is finely granular, black, scanty. Old mines soon become white and conspicuous.

I have not yet been able to study the larva.

The Cocoon.

This is a small oval structure of thin white silk within the terminal part of the mine. The roof of cuticle protecting it above is slightly thicker than elsewhere in the mine. The position of the cocoon is not a constant one, but is generally alongside the midrib or outer margin of the leaf; sometimes, however, it occupies a position between these, lying more or less at right angles to their general direction. It is most generally found about the middle third of the leaf. Dimensions, 7 mm. by 3 mm. Quite frequently the cocoon causes a slight infolding of the leaf in its immediate vicinity, but this is not so constant as in some of the other Panax moths; most generally a small hump on the upper surface of the leaf is all that reveals its existence.

In the South Island form the cocoon is constructed in a small narrow extension of the terminal part of the blotch, close to the upper cuticle of the leaf. It is usually near the outer margin of the leaf, about its middle or in its upper half. The white silken lining is very thin and frail, and causes a slight local puckering of the leaf. The small white window at the end of the cocoon is similar to that of P. panacifinens and others. Size, 6 mm. by 2 mm.

The Pupa.

All the essential characteristics are the same as in the other Panax moths. The cephalic plate is about as long as wide at its base, and the lateral cornua are short and of about half the length of the plate; the labrum is slightly above the lower margin of the eyes; mandibles prominent. Prothorax wide laterally against the antenna, but almost obliterated

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Fig. 16.—Head of pupa of P. panacivermiforma, ventral view.
Fig. 17.—Lateral view.

in the mid-dorsal region. Antennae reach to the eighth abdominal segment. Regarding the setae, these are the same as in P. panacitorsens; in the tenth segment the dorsal setae are replaced by a pair of short pointed tubercles; segment 8 bears all three pairs of setae; segment 9 bears the dorsal pair only. The two caudal appendages are well developed. The

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pupa is very active if disturbed, twirling its abdomen vigorously; two distinct movements are made, a circular twirling and a side-to-side movement. Movement takes place between segments 4–5, 5–6, 6–7, also very slightly between 2–3, 3–4. Colour at first pure crystal-white, later changing to light yellow. Just prior to emergence the wings and frontal parts become speckled grey, eyes black, upper half of antennae and legs speckled grey, lower half light yellow except for the tips. Headpiece and abdominal segments light yellow, except dorsally, where they are darker in colour.

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Chief Measurements of Pupa.
Measurement at Length from Tip of Cephalic Plate. Transverse Diameter. Ventro-dorsal Diameter.
Mm. Mm. Mm.
Base of eyes 0.23 0.52 0.42
End of labial palpi 0.86 0.69 0.65
End of first legs 1.55 0.65 0.62
End of maxillae 1.89 0.62 0.59
End of second legs 2.24 0.52 0.59
End of forewings 2.52 0.45 0.55
End of third legs 3.08 0.31 0.31
End of antennae 3.28 0.24 0.21
Extreme length 3.45

In the South Island form the antennae are as long as the body. The setal plan is identical with that of P. panacitorsens. Colour at first pearly

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Fig. 18.—Pupa of P. panacivermiforma (South Island form), ventral view.
Fig. 19.—Dorsal view.

white with a faint tinge of green; later the eyes become black, and the appendages mottled grey and white. The abdominal segments 3–6 inclusive become black dorsally, and this pigmentation remains in the cast skin.

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Chief Measurements of Pupa.
Measurement at Length from Tip of Cephalic Plate. Transverse Diameter. Ventro-dorsal Diameter.
Mm. Mm. Mm.
Base of eyes 0.51 0.65 0.48
End of labial palpi 1.21 0.76 0.72
End of first legs 2.06 0.69 0.69
End of maxillae 2.76 0.62 0.69
End of second legs 2.83 0.55 0.65
End of forewings 3.17 0.48 0.62
End of third legs 3.90 0.27 0.27
End of antennae 4.27
Extreme length 4.30

Dehiscence.

The pupa pierces the prepared window at the head of the cocoon on the upper surface of the leaf. All details as to splitting are identical with those of P. panacitorsens, and so need not be repeated.

(5.) Parectopa panacicorticis n. sp. (The Panax Bark Moth). (Plate XXX, fig. 5.)

The Imago.

♀. 7–8 mm. Head and thorax dark grey irrorated with white; palpi white with apex of second joint and subapical ring of terminal joint black; antennae grey-blackish, whitish towards apex; abdomen dark grey above, white beneath; legs white with black rings. Forewings dark grey to black, densely irrorated with white; a series of short, outwardly-oblique white marks on costa, three before ½; at ½, ⅔, and ¾ a larger wedge-shaped spot of white with a smaller one on its outer side; a narrow line of black separates the white apical spot from an indistinct band of white on its inner side; a small conspicuous white triangular area on dorsum at ½, a small white spot at ⅔ and another at ⅓; cilia white at apex, elsewhere grey. Hindwings and cilia dark grey.

In male the wing-expanse is shorter, about 6 mm.; the white markings are more conspicuous, those on costa at ½ and ⅔ especially so; the ventral surface of the abdomen is whitish tinged with grey.

This species approaches P. aethalota Meyr. very closely. I have never seen it on the wing, all my specimens being reared from pupae.

Distribution.

It is quite common on Mount Egmont at an altitude of 3,000 ft., and is plentiful in the vicinity of the Mountain House and down the mountain track. I have also found it at Dunedin in the bush behind the Botanical Gardens, and more plentifully in the Bush Reserve on Flagstaff Hill. Several old mines have been found at Aberfeldy, in the Wanganui district. The following dates give some idea as to the time of its appearance, &c.: Egmont 10/1/17, pupae found; 21/4/17, young larva; 23/12/17, many pupae obtained. Dunedin—20/17/19, a few young larvae found (these

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pupated about the middle of November); 2/12/17, many pupae found (these all emerged during January).

This little moth is attacked a great deal by a hymenopterous parasite at present unidentified.

Food-plant.

Nothopanax arboreum (whauwhaupaku).

Egg-laying.

The eggs are laid singly on the bark of the young stems of the food plant. There appears to be no especially favoured position, except that it has been noticed that the region about the expanded bases of the leaves is rarely chosen, some more or less exposed position on the internode being utilized. A description of the ovum must wait until fresh unhatched ova can be obtained. They should be looked for during the months of January and February.

The Mine.

The mine is a simple gallery throughout. At first about 0.5 mm. in width, it increases gradually to about 3 mm. The general direction is along the young stem in the internodes in its long axis. On reaching a node where the large expanded base of the leaf-stalk closely embraces the greater part of the stem the mine follows the obstruction a varying distance, eventually turning down into the next internode or retracing its way back in its old internode, turning again in a similar manner on reaching the other extremity. In this way the internodes become more or less occupied by long galleries, while at the nodes the mine may enlarge and quite envelop the stem. Blind branches are rarely found. The

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Fig. 20.—Mine of P. panacicorticis in stem of Nothopanax arboreum. (Two-thirds natural size.)

mine may at times become somewhat tortuous, and in places more or less expanded owing to several parts intercommunicating. As a general rule but one internode will be occupied by any one mine, though sometimes a mine may extend into two. Where two mines are occupying the rather small area offered by a single internode, their galleries may intermingle indiscriminately without any attempt at mutual avoidance. Such crowding is rarely found. The colour of the mine at first is white, and later white or a very pale brown; it is most conspicuous. The frass is scanty, and in the earlier portions of the mine occupies a narrow central line in the gallery. Details of the larva are reserved for a future monograph.

The Cocoon.

This structure is built in the terminal portion of the mine somewhere in the internode, very rarely against the base of the leaf-stalk. It is constructed of white silk, but is very thin, almost transparent, and is

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covered externally by the thin outer cuticle of the stem. It is somewhat cylindrical in shape, with rounded ends; average size about 10 mm. by 2.5 mm. It forms quite a conspicuous little bulge on the side of the stem, its long axis parallel to that of the stem.

The Pupa.

Of the head-parts, the cephalic plate is about twice as long as broad at its base; the lateral cornua are represented by two extremely small tubercles, only slightly elevated; labrum slightly above lower margin of the eyes. All the chief characteristics are the same as in P. panacitorsens. Individual characteristics in the Panax moths are hard to find. The forewings normally extend to the lower border of the fifth abdominal segment, while the third legs reach to the lower border of the seventh, and the antennae to that of the eighth or ninth. Regarding the setae,

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Fig. 21.—Head of pupa of P. panacicorticis, ventral view.
Fig. 22.—Lateral view.

these are the same as P. panacitorsens, with the exception that the dorso-lateral seta was present in the second segment; all three pairs were found in 8 and 9, and 10 bore a small dorsal pair and a larger dorso-lateral seta at the base of each caudal appendage. The lateral ridges are very rudimentary. The dorso-lateral setae in 2–6 inclusive are directed upwards and outwards, that on segment 3 being the longest, and in length about equal to two-thirds the width of the body at that point. Colour golden brown, darker on dorsum of head and thorax and segments 3–6 inclusive.

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Chief Measurements of Pupa.
Measurement at Length from Tip of Cephalic Plate. Transverse Diameter. Ventro-lateral Diameter.
Mm. Mm. Mm.
Base of eyes 0.76 0.69 0.51
End of labial palpi 1.41 0.79 0.72
End of first legs 2.24 0.79 0.76
End of maxillae 2.65 0.76 0.72
End of second legs 2.97 0.69 0.72
End of forewings 3.28 0.66 0.63
End of third legs 3.97 0.38 0.48
End of antennae 4.41
Extreme length 4.89
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Dehiscence.

Exactly the same as in P. panacitorsens and all the other Panax Parectopas. There is here no external evidence of any prepared exit from the cocoon, but the pupa always emerges at the uppermost end, and here also with its ventral appendages outermost.

This moth is a favourite prey to parasites, two species having been reared but not yet identified—in fact, quite 90 per cent. of all the Panax Parectopas are destroyed by these parasitic Hymenoptera. Usually there is but a single parasite to each post; this parasite constructs its small cylindrical cocoon within that of its host, and later emerges through a circular outlet gnawed in the upper end of the latter structure.

(6.) Parectopa panacifinens n. sp. (The Panax Marginal and Central Moth). (Plate XXX, fig. 6.)

The Imago.

♀, 10 mm.; ♂, 8 mm. Head whitish with a dorsal streak of fuscous; palpi whitish, with apex of second Joint and a well-defined subapical ring on terminal joint black; antennae fuscous. Thorax light fuscous with a fairly broad central line of darker fuscous, and on either side a narrow, rather obscure dorso-lateral line of dark fuscous. Abdomen grey-black; legs whitish ringed with black. Forewings brown irrorated with black; markings white, the black irrorations being somewhat denser on their margins; a narrow slightly wavy streak of white along dorsum from near base to ¾, interrupted by a small patch of brown about ⅔ (this white streak is more pronounced in the male); three distinct short outwardly-oblique white lines from costa at ⅓, ½, ⅔, the outermost one being the narrowest and longest, the centre one the most conspicuous and almost square; a narrow outwardly-concave transverse bar of white near apex, broadest against the costa; cilia fuscous with a distinct black line. Hindwings and cilia fuscous.

Distribution.

Numerous on Mount Egmont at 3,000 ft. Pupae are to be obtained during November and December, the imagos appearing in January. Also found in the Bush Reserve on Flagstaff Hill, Dunedin, in November, the imagos emerging early in December.

Food-plant.
Nothopanax arboreum (whauwhaupaku).
The Mine.

The egg is laid on the upper surface of the leaf, generally near the midrib. The mine is a simple gallery, white in colour, on the upper surface of the leaf; increases in width very gradually to about 2 mm.; its total length is about 16 in.; its character is very constant, and altogether it is a most conspicuous object. The larva on hatching burrows immediately into the leaf, and heads in in more or less of a straight line till the margin or midrib of the leaf is encountered, after which this obstacle is closely followed. Out of several hundred examined, no cases showed any tendency on the part of the newly hatched larva to mine in a spiral, as in the case of P. aellomacha. Its course invariably takes it close around the greater portion or entire margin of the leaf, closely following the digitations and

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any incursions made by other insects, and also along one or both of the sides of the midrib, this forming a barrier only in its basal three-quarters. The gallery then follows a more or less tortuous course within these boundaries; if the leaf be large it will rarely cross earlier parts of its own track, and will wander in a vermiform manner along one half of the leaf, generally that half opposite the one on which the egg was laid; in smaller leaves almost the entire upper surface will be mined in a very complicated manner, but there is never any tendency to blotch formation as in P. panacitorsens. Loops may be thrown out from the straight central portion of the gallery against the midrib, but never blind branches; this is characteristic. The way in which the gallery closely follows the margin of the leaf nearly all the way round was very characteristic of the Egmont

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Figs. 23, 24, 25.—Typical mines of P. panacifinens in leaves of Nothopanax arboreum. (Two-thirds natural size.)

mines, but was not so constant in the Dunedin ones. Perhaps the chief characteristic of the mine is the absence of blind branches. Frass is almost negligible, black, very finely granular, and is irregularly distributed. As a rule it is deposited at the margins of the mine, alternately on either side in the early parts, but later is arranged in close curved lines, convex forwards, transversely across the gallery. In the final stages it tends to become somewhat fluid in character.

The Cocoon.

The cocoon is constructed in the slightly expanded terminal part of the mine, somewhat deeper in the leaf than the rest of the gallery. Its position may be alongside the midrib, the outer margin, or one of the coarser veins of the leaf. The small cylindrical structure of white silk pulls in the cuticle of the leaf in its vicinity and causes the leaf here to become slightly elevated, puckered, and infolded, affording it greater protection. A small, thin, almost transparent white window is constructed in the upper surface of the leaf at the end of the cocoon by the larva just prior to pupation Size, about 8 mm. by 3 mm.

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The Pupa.

The pupa differs hardly at all from the other Panax moths. The cephalic plate is rather short, and about as long as wide at its base; the lateral cornua are well developed, and are about equal in length to that of the plate; in some of the Dunedin specimens, however, they were not free, but soldered down to the headpiece around the front of the base of the cephalic plate. There is a strongly marked middorsal ridge on vertex, meso-and meta-thorax, and extending slightly on to the first abdominal segment. The prothorax is narrow. Antennae variable in length, sometimes slightly longer than the body. Setae exactly as in P. panacivermiforma.

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Fig. 26.—Head of pupa of P. panacifinens, ventral view.
Fig. 27.—Lateral view.

[The section below cannot be correctly rendered as it contains complex formatting. See the image of the page for a more accurate rendering.]

Chief Measurements of Pupa.
Measurement at Length from Tip of Cephalic Plate Transverse Diameter Ventro-dorsal Diameter.
Mm. Mm. Mm.
Base of eyes 0.72 0.79 0.55
End of labial palpi 1.51 0.96 0.90
End of first legs 2.53 0.90 0.86
End of maxillae 2.86 0.86 0.86
End of second legs 3.51 0.72 0.86
End of forewings 3.90 0.69 0.83
End of third legs 4.89 0.48 0.51
End of antennae 5.45
Extreme length 5.65

Dehiscence.

Exactly as in P. panacivermiforma.

(7.) Parectopa aellomacha Meyr. (The Panax Branching Moth).
(Plate XXX, fig. 8.)
Gracilaria aellomacha Meyr., Trans. N.Z. Inst., vol. 21, p. 184, 1889.
Parectopa aellomacha Meyr., Trans. N.Z. Inst., vol. 47, p. 228, 1915.

Meyrick's Original Description.

“♂♀. 7–9 mm. Head and palpi snow-white, palpi with apex of second joint and a subapical ring of terminal joint black. Thorax snow-white, with a small black spot on shoulder. Forewings snow-white; markings fuscous, irrorated with dark fuscous; a cloudy central longitudinal streak from near base to disc above anal angle, more or less obsolete towards base, connecting obscurely with about seven oblique costal and about four

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oblique dorsal streaks (these vary somewhat); costal streaks usually alternately slender and thick; a fuscous apical spot: cilia grey, round apex white, with two dark fuscous lines and a black apical hook. Hindwings fuscous-grey, cilia paler.”

Distribution.

I have so far found this species only on Mount Egmont, about 3,000–4,000 ft., where it is quite plentiful. Pupae were obtained during December and January, emerging in February. Young larvae were found in April of 1917. Meyrick records it from “Wellington and Christchurch, in September, January, and February; four specimens.

Food-plant.

Nothopanax arboreum (whauwhaupaku).

The Mine.

The mine is a most characteristic one. It is rare to find more than one mine in a leaf. The egg is invariably laid upon the upper surface near the midrib, and generally in the basal portion of the leaf. The larva on hatching at once mines into the leaf through the shell of the egg, and as a general rule takes several spiral turns before mining in any definite direction. This spiral nature of the earliest portion of the mine is characteristic. The mine throughout is a very gradually widening gallery, never becoming blotched, and rarely do portions cross each other except in the smaller leaves. The final width is about 2 mm. Its direction invariably takes it

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Figs. 28, 29.—Mines of P. aellomacha in leaves of Nothopanax arboreum. (Two-thirds natural size.)

along both sides of the midrib, this obstacle being crossed in its upper and thinner part; from these long straight portions a varying number of blind arms or branches of varying lengths, mostly straight but sometimes slightly curved, sprout out into the leaf. As a rule the greater number will be confined to one half of the leaf. These blind branches sometimes follow the course of the veins of the leaf, but most often do not, generally treating these as no obstacle; they do not often reach as far as the outer margin of the leaf, but may do so, and may follow it a short distance; the result is, however, always the same—a single blind-ended branch, never loops as in the case of P. panacifinens; and rarely is any of the margin of the leaf so mined. The branches are all more or less parallel to one another, and rarely cross; they are all more or less equal in width, about 2 mm. The mine is found only in the younger leaves, and is pale green in colour, the tips of the branches often being white, showing where the larva came close against the upper cuticle. No evidence of the mine is to be found on the underside of the leaf, and in its natural state the mine is not a very conspicuous

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object, though so very striking when seen in picked leaves. Old mines become white, but otherwise do not discolour the leaf; they are consequently far more conspicuous objects than the fresh ones. The mine is slightly deeper in the leaf than that of P. panacifinens. The total length of the mine may reach to 12 in. or 16 in. Frass is very finely granular; negligible.

The Cocoon.

The cocoon is a somewhat cylindrical structure of thin white silk, with all the characteristics of P. panacifinens. It is within the mine in the upper part of the leaf, and is protected by a somewhat thicker covering than the rest of the mine. It is slightly elevated, and as a rule causes a local pinching of the leaf. It is invariably found alongside the midrib in the basal third of the leaf. Size, 7 mm. by 2 mm. Its small white window is quite conspicuous at the head end of the structure; it is fan-shaped, with its broadest part upon the surface of the leaf. Old cocoons soon become discoloured brown.

The Pupa.

The pupa of this moth is practically identical with that of P. panacifinens; on the average it may be slightly smaller; its lateral cornua are relatively more developed, and are about one-half the length of the cephalic plate. The arrangement of the setae is the same in both, but in aellomacha the dorsal setae are short and fine, the dorso-lateral ones rather stout and long. The following measurements were taken from a typical specimen:—

Chief Measurements of Pupa.
Measurement at Length from Tip of Cephalic Plate. Transverse Diameter. Ventro-dorsal Diameter.
Mm. Mm. Mm.
Base of eyes 0.69 0.76 0.63
End of labial palpi 1.44 0.86 0.79
End of first legs 2.76 0.79 0.76
End of maxillae 3.03 0.69 0.76
End of second logs 3.28 0.63 0.69
End of forewings 3.65 0.51 0.60
End of third legs 4.55 0.38 0.35
End of antennae 5.03
Extreme length 5.59

Dehiscence.

This takes place on the upper surface of the leaf, and is identical with that of P. panacifinens.

(8.) Parectopa panacivagans n. sp. (The Lancewood Parectopa).
(Plate XXX, fig. 10.)

The Imago.

8 mm. Head white at the sides, black above and against thorax; palpi white with two black rings; antennae black suffused with white below and towards base. Thorax white, black against the head, and caudally a small black V-shaped mark; legs white with black rings. Abdomen blackish grey. Forewings black, slightly irrorated with white; markings white; from base to ¼ white with a small central spot of black; a short narrow outwardly-oblique line of white on costa at ⅓, another slightly larger and triangular spot a little beyond ½ reaching half across wing; a short narrow oblique line of white at ¾; an indistinct inwardly-curved

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transverse line of white near apex; a small white apical spot; a broad outwardly-oblique line of white on dorsum at ½, and a small white spot at ¾; cilia grey-black. Hindwings dark grey; cilia grey-black.

Distribution.

This appears to be a rather rare moth. It was found first at Aberfeldy, in the Wanganui district, in 1917. The larvae are to be found in December, the pupae in January, and the imagos emerge in February. Old mines were found in Dunedin in May and July.

Food-plant.

Found mining in the long tough leaves of the young lancewood, Pseudopanax crassifolium (horoeka), but more commonly in the young succulent leaves of the mature tree.

Egg-laying.

The egg is laid singly on the upper surface of the leaf, generally close to the midrib.

The Mine.

The mine throughout is a simple gallery, more or less straight in its direction. It is made entirely in the upper surface of the leaf, and there is no trace of it to be seen below. The mine starts in a more or less oblique direction till it reaches the midrib or margin of the leaf; this it follows till it reaches the end of the leaf, and it then either turns back alongside its former track or continues back along the barrier on the other half of the leaf. It never crosses the midrib except in its upper part. On the margin of the leaf the mine closely follows all the irregularities of outline, and extends into the bases of the serrations of the leaf. Portions of the earlier mine may be enveloped by the later broader

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Fig. 30.—Mine of P. panacivagans in the lancewood-leaf. (Two-thirds natural size.)

gallery. The average length may be about 10 in.; commencing with a width of 0.5 mm., the terminal part of the gallery measures about 4 mm. across. Colour light green in fresh mines. There is no tendency to branch. Margins of the mine fairly regular and white. Mines are not very conspicuous at a short distance. Frass is almost fluid in nature, and occupies a fairly broad brown band in the centre of the early gallery, but in the wider part is dark green or black, and often forms an unbroken line on one side of the gallery; it is sometimes deposited in short curved transverse lines with the concavity directed forwards. It appears to be deposited chiefly on the upper cuticle of the leaf.

The Larva.

Flattened, moniliform; colour yellowish with broad green dorsal stripe. About 6 mm. in length. A detailed description is kept for a future paper on the Parectopa larvae.

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The Cocoon.

The cocoon is constructed within the terminal part of the mine, either close alongside the midrib or on the outer margin of the leaf. It is slightly deeper in the substance of the leaf than the rest of the mine. It is cylindrical in shape and slightly curved. The scanty silken lining causes a local pinching and puckering of the leaf, and raises the cuticle above the surface of the leaf. It bears a small white almost transparent window at one end, prepared for the pupal emergence. Its position is generally in the basal half of the leaf. Size, 12 mm. by 3 mm.

The Pupa.

Closely resembles the pupa of the Panax moths in all particulars. The cephalic plate is moderate in length, but fairly massive; the lateral

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Fig. 31.—Pupa of P. panacivagans, ventral view.
Fig. 32.—Dorsal view.
Fig. 33.—Lateral view.

cornua are about equal in length to the plate. Prothorax broad against the antennae, but is lost in the mid-dorsal region. Setae exactly as in P. panacitorsens; the lateral setae are relatively long.

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Chief Measurements of Pupa.
Measurement at Length from Tip of Cephalic Plate. Transverse Diameter. Ventro-dorsal Diameter.
Mm. Mm. Mm.
Base of eyes 0.53 0.70 0.53
End of labial palpi 1.29 0.82 0.76
End of first legs 2.12 0.76 0.76
End of maxillae 2.65 0.70 0.76
End of second legs 2.82 0.70 0.76
End of forewings 3.18 0.65 0.53
End of third legs 3.88 0.41 0.35
End of antennae 4.65
Extreme length 4.65
Dehiscence.

This takes place on the upper surface of the leaf and is identical in all respects with that of the Panax moths.