Part 16

Abundant in the forest, where it may be dislodged from ferns and undergrowth during the day or captured flying about in the evening. Its larva is rather attenuated, and possesses a large hump on the second abdominal segment. In colour it is dark reddish brown, mottled with creamy white and pale green, and is sparsely supplied with a few isolated hairs (Fig. 1b). It feeds on the white rata (Metrosideros scandens), and when in its usual position--i.e., sticking straight out from a branch--absolutely defies detection. Specimens, however, may be readily procured with a lantern at night, when they may be found walking about and eating. The pupa state is spent in the earth, about two inches below the surface, the moth appearing in three or four weeks' time, this period, however, being extended in the case of autumnal larvæ, to as many months. It is extremely variable, scarcely two individuals being found exactly alike. The colouring, as in the caterpillar, is chiefly protective, consisting of a delicate tracery of browns and greys, which render the insect quite invisible when resting on the trunk of a tree, with its pale yellowish hind-wings concealed, a position it invariably assumes {91}during the daytime (Fig. 1 male, 1a female). The curious and interesting "Tatosomas," with their enormously elongated bodies, are closely allied to the present insect; one of them (Tatosoma agrionata) being found in similar situations, although in much more limited numbers; as, however, I know nothing of their transformations, I am forced reluctantly to pass them by.

Family GEOMETRIDÆ.

Hydriomena deltoidata (Plate XIII., fig. 1, 1a larva).

One of our commonest moths, appearing in great numbers during January and February, in all open situations. It is especially abundant on the fern-hills.

The larva (Fig. 1a) feeds on the plantain. It is very sluggish, and lives all through the winter, becoming full-grown in September, when it changes into a pupa, among the roots of its food-plant. In colour it is a uniform dark brown.

The moth is extremely variable, but the figure may be taken as representing a fairly typical specimen. It is a pretty insect, and may be often seen resting on fences with its fore-wings folded backwards and forming together a triangle, whence its name of deltoidata. Any unusual-looking specimens of this species should always be netted, in order to form a thoroughly representative series, as many of the varieties are very interesting. A rather uncommon and remarkable-looking form occasionally occurs, in which the dark central band of the fore-wings is completely divided near the middle.

Family GEOMETRIDÆ.

Asthena schistaria (Plate XII., fig. 2, 2a larva).

This delicate little insect may be often taken at rest on fences and tree-trunks during the day, and is a {92}conspicuous moth when flying in the evening, owing to its light colour. The larva (Fig. 2a), which feeds on the manuka (Leptospermum ericoides), is very ornamental. Its general colour is light green, with black dorsal and lateral stripes, and a series of diagonal markings bordered with crimson; the legs and prolegs are also crimson, and the segments are divided by brilliant yellow rings, a white line extending down each side of the larva. It is difficult to find, as it remains closely concealed amongst the dense manuka foliage, from which it can only be dislodged by vigorous and continued beating. The caterpillars allow themselves to fall a short distance, hanging suspended by a silken thread, which they rapidly ascend when the danger is passed. The pupa is rather attenuated, dark-brown, and much pointed at its posterior extremity. It is found buried about an inch in the earth, and the moth appears in a month's time. This insect varies much in intensity of markings. The males are generally considerably darker than the females, but are more certainly distinguished by their attenuated bodies.

The pearly white Asthena pulchraria occurs in October and April; it is a most beautiful insect, and may be found amongst the foliage of the kawakawa (P. excelsum), on which its larva will probably be found to feed.

Family PYRALIDÆ.

Scoparia hemiplaca (Plate XII., fig. 4).

This pretty little moth was reared from a larva found feeding amongst moss during the winter of 1885, but unfortunately I neglected to make a drawing until it was too late. Doubtless many of the other Pyrales we meet with in the New Zealand forest have similar habits, their larvæ probably feeding on different kinds of mosses. These can always be examined during the winter months, {93}when the entomologist is usually in want of work, and thus much information may be obtained regarding this interesting but little-known family.

Family PYRALIDÆ.

Scoparia sabulosella (Plate XIII., fig. 4, 4a larva).

This is that extremely abundant, though dull-coloured little insect, that rises in such multitudes from every field before one's footsteps during the early summer.

Its larva (Fig. 4a) feeds on various mosses, forming numerous silken galleries amongst the roots in which it resides. These caterpillars are very active, and consequently rather difficult to obtain, as they move either backwards or forwards in their galleries with equal rapidity.

They feed during the whole of the autumn and winter, changing into pupæ about September, from which the moths emerge in a month or six weeks' time.

The habits of the numerous other species belonging to this genus and the closely allied genus Xeroscopa (Meyr) probably do not materially differ from those of the species here described.

Family PYRALIDÆ.

Crambus flexuosellus (Plate XII., fig. 5).

An extremely abundant insect, occurring in swarms over meadows during the summer, where it may be captured in the daytime or taken by hundreds at the attracting lamp in the evening. Its larva is at present unknown, but probably feeds on the roots of grasses.

Closely allied is Crambus tahulalis, found in similar situations, but appearing rather later in the season, the earliest specimens being met with about January, while C. flexuosellus is on the wing throughout the summer.

{94}Family PYRALIDÆ.

Siculodes subfasciata (Plate XII., fig. 3, 3a larva, 3b pupa).

This curious insect may be occasionally taken flying round patches of Muhlenbeckia adpressa, which grows freely amongst brushwood in many parts of the country.

Its larva (Fig. 3a), is very stout and sluggish, resembling the caterpillar of an ordinary Pyrale in general appearance. It feeds in the stems of the creeper, causing large swellings therein, which readily betray its presence, and should therefore be cut off and kept until the moth emerges, as specimens obtained in this way are far superior to any captured in the open. The pupa is dark brown, and shining; it lies in the centre of one of the swellings, the larva having previously prepared a safe outlet for the moth in the form of a small burrow leading to the air, its extreme end remaining closed by a thin pellicle of the original bark, which effectually prevents the inmate's resting-place being discovered from the exterior (see Fig. 3b, the small circle marked * represents the outlet).

The perfect insect appears about December, flying rapidly in the hottest sunshine. It varies greatly, both in size and colour, some of the small males being very much suffused with dark brown, while the females usually resemble the figure (3), and are often more than twice the size of their mates. This insect is generally placed in a family called the Siculidæ, but I think without sufficient reason, and have therefore located it among the Pyralidæ, with which it has unquestionably a great affinity.