Part 41

Genus 11.--XANTHORHOE, Hb.

"Face with somewhat projecting scales or conical tuft. Antennæ in male bi-pectinated, apex usually simple. Palpi rough-scaled. Fore-wings with areole double. Hind-wings with vein 8 anastomosing with cell to beyond middle."--(Meyrick.) (See Plate II., figs. 37 and 38.)

{57}This interesting genus is relatively far more numerous in New Zealand than elsewhere, its place in other regions being largely taken by Hydriomena. We have no less than thirty-one known species, and many others will no doubt be ultimately discovered, especially in the mountainous districts of the west coast of the South Island.

XANTHORHOE LIMONODES, Meyr.

(Epyaxa limonodes, Meyr., Trans. N. Z. Inst. xx. 54.)

(Plate VII., fig. 46 .)

This species has occurred at Wellington and at Cape Terawhiti in the North Island.

The expansion of the wings is about 1 inch. The fore-wings of the male are dull olive-green with numerous, rather obscure, wavy brownish transverse lines; these lines are all more distinct near the costa; there are two transverse rows of white dots near the base, a very broken line of white dots at about three-fourths, one of the dots forming a crescentic mark above the middle; beyond this line the colour is often paler, especially towards the apex, but inside this line there is often a considerably darker patch; there is a very distinct blackish patch just below the apex. The apex of the wing slightly projects, and the termen is arched. The hind-wings are very pale greenish-ochreous; there is an obscure dusky transverse line in the middle. The female has the fore-wings much browner; there are several additional rows of white dots and two conspicuous white spots above the middle.

The species is rather variable. In many specimens the dorsal half of the fore-wing is much paler than the costal half.

The perfect insect appears from November till March, and frequents dense forest. It is not a common species.

XANTHORHOE SUBDUCTATA, Walk.

(Larentia subductata, Walk. 1198. Epyaxa subductata, Meyr., Trans. N. Z. Inst. xx. 55.)

This species has occurred at Auckland.

"The expansion of the wings of the female is 26 mm. (about 1 inch). Head, palpi, and thorax pale greyish-ochreous, somewhat mixed with yellow-greenish, and densely irrorated with fuscous. Antennæ whitish-ochreous annulated with fuscous. Abdomen grey-whitish, densely irrorated with fuscous. Legs dark fuscous, apex of joints ochreous-whitish, middle and posterior pair irrorated with grey-whitish. Fore-wings with costa gently arched, termen waved, slightly rounded, oblique; pale greyish-ochreous, mixed with yellow-greenish, and thinly sprinkled with fuscous, tending to form faint waved lines; three light fuscous fasciæ, each marked with three dark fuscous lines; first near base, outer edge sharply angulated above middle; second from two-fifths of costa to before middle of dorsum, slightly curved; third from two-thirds of costa to two-thirds of dorsum, outer edge somewhat prominent in middle, rather sinuate above it; a crescentic black obscurely whitish-margined discal spot; a short oblique cloudy fuscous streak from apex; cilia light fuscous, somewhat sprinkled with whitish. Hind-wings light grey; a grey discal dot before middle; a median band of three darker lines, outer rather prominent in middle; faint indications of other darker lines, most distinct posteriorly; cilia grey-whitish, with two cloudy grey lines."--(Meyrick.)

The perfect insect appears in December.

XANTHORHOE ROSEARIA, Dbld.

(Cidaria rosearia, Dbld., Dieff. N. Z. ii. 285, Butl., Cat. pl. iii. 13. Coremia ardularia, Gn., E. M. M. v. 63. Coremia inamænaria, Gn., E. M. M. v. 63. Epyaxa rosearia, Meyr., Trans. N. Z. Inst. xvi. 71.)

(Plate VII., fig. 22 , 23 .)

This species has occurred at Wellington in the North Island; and in the South Island at Akaroa, Christchurch, and Dunedin.

{58}The expansion of the wings is about 1-3/8 inches. The fore-wings of the male vary from pale pinkish-grey to pale greenish-grey; there is an obscure darker basal area, a rather broad central band, formed of numerous shaded, wavy, dark grey lines, which are generally absent towards the middle of the band; there is a black dot above the middle; the termen is shaded with dark grey, and there is an oblique pale mark near the apex. The hind-wings are grey with a few very faint wavy lines. The cilia of all the wings are pinkish-grey. The female is dull yellowish-grey, with the markings very indistinct.

Both sexes vary slightly in the ground colour, and in the intensity of the markings. Mr. Purdie has pointed out that the species is very liable to fade, and hence it appears to vary more than is actually the case.

The eggs are oval, pale yellow, changing first to orange, and then to dull grey before hatching. The young larva, when first emerged, is pale greyish-brown and very slender. Later on the caterpillar becomes dull olive-green speckled with black; there are two paler stripes just below the middle of the back, then a fine black line, followed by a very fine white one, then a broad pink stripe on the side; below this is a broad black line followed by a white line and two fine black ones. The larva is moderately stout, and the two prolegs are very close together.

The larva, when full-grown, measures about ¾ inch in length. The general colour is dull reddish-brown, often greenish-tinged. The back and sides are marked with numerous slightly waved fine black lines; there is a double series of black dots down the back, a broad black lateral line, followed by a fine white line. The under side of the larva is pinkish-brown; the head greenish-brown speckled with black. The caterpillar is obscurely marked, and very variable. It is often clouded with greenish colouring.

The food-plant is watercress.

The pupa, which is enclosed in a slight cocoon constructed of earth and silk, is found on the surface of the ground.

The perfect insect is most abundant in December, and is attracted by light. It seems to be about during the entire year, as Mr. Meyrick states that he has taken numerous specimens from May till September, and hence concludes that it is essentially a winter species. I can to some extent confirm this observation, as I have also found the insect during the winter, although not commonly. It is probable that there are several broods in the course of a year, and that the species hibernates as an imago.

Regarding the synonymy of this species Mr. Meyrick remarks that "C. ardularia, Gn., is the male and C. inamænaria, Gn., the female of this species. C. subidaria, Gn., quoted by Butler as a synonym, is an Australian species, and not identical."

XANTHORHOE OROPHYLA, Meyr.