[Read before the Wellington Philosophical Society, 7th June, 1921; received by Editor, 9th June, 1921; issued separately, 17th February, 1923.]

Since the appearance of Hutton's important papers on the Stenopelmatidae of New Zealand nothing has been published on the Orthoptera living in the limestone caves of New Zealand.^* All, therefore, that this author said in his first paper concerning those insects can still be considered as true. Speaking of the various species of Rhaphidophorinae found in caves, Hutton said, “The cave wetas are in the greatest confusion, and we do not know whether there are six or only two species.”

This confusion is due to the fact that most of those species are known from a few examples only, and have generally been quite insufficiently described. Dr. J. Allan Thomson, Director of the Dominion Museum, Wellington, having kindly sent me for examination a small number of insects recently collected, I have had available a comparatively large amount of material, including fourteen specimens, belonging to three species, from the British Museum, very kindly communicated by Dr. Urarof. Besides this, Professor R. Ebner was recently good enough to send me the types of Rhaphidophorinae of Brunner's collection, among which I found Neonetus

As far as I am aware, no representative of this remarkable genus has until now been found in the South Island. I do not think there is more than one species in the North Island, although local varieties may possibly exist.

Pachyrhamma fascifer Walk.

Kaiparora (Wellington), 16th March, 1917; one male, one female. Karori (Wellington), (cave), 1916; two females, two males; one young male, two young females.

A good redescription of this species has been given by Hutton,^* to which need only be added that the subgenital plate of the female is small, triangular, presenting a wide semicircular notch at apex, the ovipositor rather longer than the body, almost straight, its inferior valves showing before the apex 10 small transverse ridges.

The number of spines of the legs is somewhat variable, as shown by the following table:—

The high specialization of the antennae of the males in this species proves somewhat different according to the specimens examined. In some of them the joints are cylindrical and smooth to about the sixtieth; they begin then to show a small apical tooth beneath till about the hundredth joint. This tooth becomes stronger but irregular towards the apex of the differentiated region, which region ceases abruptly, the joints again becoming cylindrical and very hairy. In others the joints are differentiated from the twentieth on, showing alternately small and

large teeth until the seventieth or eightieth joint, where the antennae become cylindrical and hairy as stated above. In immature specimens the antennae show no differentiation whatever, appearing very much like those of the female, but rather thicker at base.

These differences seem quite individual; whilst another character may be considered as a real male dimorphism, as formerly related by Griffin among Stenopelmatids.^* The two adult males found at Karori present a rather bigger head, with larger, strongly-notched eyes, and antennae thicker at base. They really seem somewhat different from the males of Kaiparora, but, both unfortunately lacking the apex of the abdomen, it is impossible to state whether they differ in other characters.

It may be added that P. fascifer does not seem to be exclusively cavernicolous, as I received a female from Mana Island which has certainly been caught outside of caves. Very likely the species has a mode of living similar to that of our European Dolichopoda or Troglophilus.

Pleioplectron cavernae Hutt.

Cave near Taupo, F. W. Hutton, 18th February, 1899; one male, one immature female (British Museum).

A few peculiarities must be added to Hutton's description of this species.

Frontal rostrum narrow, compressed, deeply and very narrowly notched at apex; palpi almost white, maxillary palpi not very long, with fourth joint equal to third, fifth once and a half as long as fourth (length of the three joints, 2 mm., 2–2 mm., 5–3 mm., 5 mm.). Anterior femora without apical spines or with a very small internal one; tibiae hairy, with 2 apical spurs and 3 spines on each inferior margin. Middle femora with a short external apical spine and a rather long, movable, internal one; tibiae with 4 apical spurs, 4 spines above (3 external, 1 internal), and 3 on each inferior margin. Posterior femora armed with a small genicular internal spine, 6–7 rather strong ones on the inferior internal margin, and only 2 small ones near the apex of the external margin; tibiae cylindrical and glabrous, presenting a brown ring near the base, and armed on each superior margin with 25–30 very small, brown, widely-separated, irregular spines, the last of which is apical; spurs short, the external a little longer than the internal ones, inferior ones very short, spiniform, intermediate half as long as the superior ones. Tarsi long, almost glabrous, very little compressed beneath, rounded above, first and second joints with 2 apical spines; metatarsus as long as other joints together, armed with 4–6 small spines, on two rows, besides the 2 apical ones.

Tenth tergite of male large with its posterior margin wide, weakly concave, rounded angles; anal valves very small; subgenital plate large, presenting a basal part wide and little convex, and an apical one projecting between the styles, triangular, subacute at apex, furrowed beneath; styles very short, cylindrical, inserted about on the middle of the lateral margins of the plate. Cerci rather long, straight, almost as thick at apex as at base.

I have seen no adult female, but the subgenital plate of the immature one shows a rounded notch at the apex.

If it is not an accidental disposition of the specimen here described, this species shows a very remarkable character in the apical spurs of the posterior tibiae; I think it is quite an exception in the whole group of the Rhaphidophorinae to have the internal spurs shorter than the external ones. If this feature be confirmed by examination of other specimens I should not hesitate to consider it as of generic value; but it seems so extraordinary that I cannot decide the question, chiefly from the fact that only one leg of the two specimens I have seen was in good condition for study.

I cannot follow Hutton's conclusions as to the synonymy of this species with Pachyrhamma edwardsii Br. (non Scudd). Brunner's description of the latter species runs as follows: “Femora antica subtus inermia, postica longissima, gracillima, subtus margine interno spinis 4–6 longioribus, margine externo spinulis minimis confertissimis armata.” This character is in absolute contradiction with what we observe and what Hutton himself has described in P. cavernae.

Frontal rostrum very narrow, truncated and feebly notched at apex; antennae very close at their base. Lateral lobes of pronotum only moderately high, their inferior margin straight. Cerci rather short and thick, little acute at apex. Anterior and middle femora armed with 2 acute movable spines, fore and middle tibiae with 4 apical spurs; posterior femora rather short, unarmed beneath, bearing a short internal genicular spine; posterior tibiae rather pubescent, armed with about 35 irregular spines; 4 apical spurs only, of which the supero-internal are longer than half the metatarsus. Male: Seventh, eighth, and ninth abdominal sternites partially united, and with the genital valves form a very remarkable genital complex. Female: subgenital plate small, ovipositor rather long, almost straight.

Genotype.—Weta thomsoni n. sp.

This genus takes place between Miotopus Hutt. and Neonetus Br., having movable acicular spines at apex of fore and middle femora and 4 apical tibial spurs; but the most remarkable feature consists in the form of male genitalia, which alone would need the creation of a new genus for the species.

Weta thomsoni n. sp.

♂. Medium-sized, rather slender species, with shining teguments, rather scarce pubescence, coloration yellowish, marbled with brown.

Head as large as the pronotum, yellowish; occiput convex, rather long, presenting a fine brown line behind each eye; frontal rostrum brown, very narrow, truncated and little notched at apex, furrowed on its whole length; two very neat ocellar spots at its base. Face yellow, with golden rather abundant pubescence; a rather large, badly defined brown spot beneath each antenna. Eyes small, black, situated rather high behind the antennae. Mouth-parts short; maxillae with 2 apical and very slender ante-apical teeth; palpi whitish, with first joint short, second rather long, third long and rather thick, fourth equal to third, fifth long, little curved

the apex; in the middle of the tibiae the spines are disposed in short series, as shown by the following formulae:—

11—3–2–3–4–2–2–3–2–2–1–1–1–1–1– = 39.

11–4–3–2–2–1–1–2–1–2–1–1–2–1–1–1 = 36.

Only 4 apical spurs, the inferior not half as long as the superior ones, the latter very long, extending over the half of the metatarsus; this (the metatarsus) is armed above with two rows of 4 to 6 small spines, the first of which is rather distant from the others, the pair nearer the apex the stronger; beneath it bears two rows of very small spinules almost to the apex; second joint armed above with 3–4 spines on each margin. The posterior legs are rather pubescent.

♀. In general shape and colour similar to the male; supra-anal valve smaller, quadrangular, somewhat notched at apex, presenting a slight median elevation; subgenital plate very small, almost hidden between the seventh sternite and the base of ovipositor, rounded or little notched at apex. Cerci as in male but slightly more acute at apex. Ovipositor moderately long, almost straight, little enlarged at base, curved and acuminate at apex; inferior valves with 7 rather strong denticulations, superior ones longitudinally striated outside, acute at apex.

Length of body, ♂ 23 mm., ♀ 18 mm.; pronotum, ♂ 5 mm., ♀ 4·5 mm.; anterior femora, 9·5 mm.; anterior tibiae, 9·5 mm.; internal femora, 9·5 mm.; internal tibiae, 9·5 mm.; posterior femora, 15 mm.; posterior tibia, 19 mm.; posterior tarsus, 9 mm.; posterior metatarsus, 4·7 mm.; superior internal spur, 3 mm.; cerci, 3·6 mm.; ovipositor, 10 mm.

I take pleasure in naming this species in honour of Dr. J. Allan Thomson.

Types.—One male, one female, from limestone cave, Opihi River, near Raincliff, South Canterbury, 4th May, 1917.

Co-types.—Male and female, same locality.

This genus was established by Brunner von Wattenwyl for a small species which the said author described so briefly that it was quite impossible to recognize it when a second species of the genus was discovered subsequently. For that reason Hutton thought it best to select the commonest species as type of the genus, and consequently selected N. variegatus Br. As I stated, I had the opportunity of examining Brunner's types, and I found that his variegatus was quite different from what Hutton had thought it, and was much more closely related to pilosus Hutt.; the form of the subgenital plate of the male seems very comparable in both species, but variegatus does not show the abundant hair-clothing given by Hutton as characteristic of his pilosus. A full redescription of N. variegatus Br. seems therefore necessary.

Neonetus variegatus Br.

Neonetus variegatus Brunner, 1888, Verh. zool. bot. Ges. Wien, xxviii, p. 300, pl. 7, fig. 27 (non Hutton, 1897).

Rather small species, with a testaceous-brown coloration marbled with numerous light, dark-brown-circled spots; pubescence rather scarce. Head small, rounded; frontal rostrum very narrow, compressed, forming two small tubercules, little acute, truncated, and feebly divided at apex, deeply furrowed above; face yellowish with a brown spot beneath each eye and a wide brown band on each side from the antennal socket to