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 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).