Part 77

The best time of year to obtain the pupa of this insect is during August and September, as most of the specimens are then in that condition. Apart from the indications above described, burrows containing larvæ may often be known by the fresh pellets of excrement which are present near the opening. The vacated burrows frequently have the remains of the old pupa shell at the entrance, and generally look gnarled and weather-worn. These indications are useful as guides to the collector before exploring the burrow with a straw in the manner above described.

This insect is much attracted by light, and in consequence sometimes enters shop-windows and houses. In fact nearly all the captured specimens are so taken, the moth being very rarely found in its native forests. This circumstance is no doubt due to its very perfect protective colouring which, notwithstanding its large size, causes it to be almost invisible, when resting on the branch of a tree. On one occasion I discovered a specimen in this situation; being obliged to leave it for a short time, I experienced the utmost difficulty in finding it again, although I had taken a special note of its position. This species appears to be much persecuted by insectivorous birds, as we may frequently see its large green wings lying on the ground, where they are very conspicuous.

{132}Genus 2.--PORINA.

"Antennæ ¼-2/5, in male bi-pectinated, or more or less shortly bi-dentate. Palpi moderate, porrected, basal joint rough-haired, second joint rough-haired or almost smooth, terminal joint smooth, sometimes subclavate. Posterior tibiæ densely rough-haired. Fore-wings with vein 7 from angle of cell, 8 and 9 out of 10, rising from upper margin much before angle. Hind-wings as in fore-wings."--(Meyrick.) (Plate I., figs. 28 and 29 neuration of Porina signata.)

Of this genus we have eight species in New Zealand.

PORINA DINODES, Meyr.

(Porina dinodes, Meyr., Trans. N. Z. Inst. xxii. 206.)

(Plate XIII., fig. 8.)

This handsome species was discovered at Invercargill by Professor Hutton.

The expansion of the wings is 2¾ inches. The fore-wings are dark brown. There is an irregular white mark with a brown centre at the base, several white dots and crescentic marks near the middle, an oblique series of double crescentic marks followed by a considerably fainter series near the termen. The hind-wings are yellowish-brown; the cilia of all the wings are white, barred with dark brown. The antennæ of the male are strongly bi-pectinated.

Described and figured from a specimen in Mr. Fereday's collection.

PORINA MAIRI, Buller.

(Porina mairi, Buller, Trans. N. Z. Inst. v. 279, pl. xvii., Meyr., Trans. N. Z. Inst. xxii. 207.)

A single specimen of this fine species was discovered by Sir Walter Buller on the Ruahine Ranges, in the Wellington district, during the summer of 1867.

The expansion of the wings is about 5 inches. "Wings large, broad, front-wings produced, ovate-triangular, pale dirty testaceous; six black spots terminating veins on outer margin, and bounded by a lunated marginal white band; a submarginal series of arrow-headed black spots, and beyond these a series of rounded spots, the first four encircled with white, the rest with pale brown; two broken, black discal lines filled in with brown; a broad irregular band to below centre of wing, beyond cell, and formed of three black lines with brown interspaces; a triangular white spot below cell and a white patch terminating it and traversed by two black crosses; two diverging black bars surrounded with white in centre of cell and a third surrounded with dirty testaceous near base; a large irregular patch of whitish-brown below end of cell, bounded on internal area by three unequally formed patches which together almost form the sides of a large triangle; two small spots near base; hind-wings greyish, becoming browner towards outer margin and crossed by eight interrupted black bars."--(Buller).

The type specimen of this species was unfortunately lost in the wreck of the barque 'Assaye' in 1890. I have copied the above from Sir Walter Buller's original paper, and it may be well to point out that his description proceeds from the termen to the base, being the reverse order to that followed by me in all the other descriptions in this work.

The so-called "vegetable caterpillar" (infested with the Sphæria fungus [Cordiceps robertsii]) is, I think, very probably the larva of this insect. It was formerly supposed to be the larva of Hepialus virescens; but I have pointed out elsewhere that this is certainly erroneous, the larva of H. virescens living in the stems of trees, and never going beneath the ground, even to pupate, whilst the "vegetable" larva is subterranean. The real point to be discovered is the precise species of Lepidoptera this caterpillar would develop into, if not attacked by the fungus; but at present no definite information has been obtained on the subject.

{133}PORINA ENYSII, Butl.

(Porina enysii, Butl., Proc. Zool. Soc. Lond., 1877, 381, pi. xlii. 7. Porina enysii, Meyr., Trans. N. Z. Inst. xxii. 207.)

(Plate XIII., fig. 9 , fig. 10 .)

This species appears to be confined to the North Island, where it is rather rare.

The expansion of the wings of the male is 2½ inches, of the female 3½ inches. The fore-wings are dark orange-brown, more or less marbled with yellow and dark brown; there is a very variable number of small dull white spots margined with black and arranged irregularly on the wing. The hind-wings are pinkish-brown, tinged with ochreous on the termen.

This species varies a good deal in the extent of the darker markings, and number and position of the dull white spots. When alive it is usually very strongly tinged with pink.

The perfect insect appears in December and January, and frequents forests. It is especially fond of resting on the stems of tree-ferns in the daytime, where, however, it is extremely inconspicuous, and can only be discovered by very careful searching. It is also very partial to light, and specimens might perhaps be secured more plentifully, if a good attracting lamp were exhibited in a suitable locality.

PORINA CHARACTERIFERA, Walk.

(Hepialus characterifer, Walk., Suppl. 594. Oxycanus impletus, ib. 598. Porina characterifera, Meyr., Trans. N. Z. Inst. xxii. 208.)

(Plate XIII., fig. 11 .)

This fine species has been taken in the North Island at Auckland, Kaitoke, and Wellington.