This caterpillar is difficult to find, as it remains closely concealed amongst the dense Manuka foliage, from which it can be dislodged only by vigorous and continued beating. The larvæ allow themselves to fall a short distance, hanging suspended by a silken thread, which they rapidly ascend when the danger is past.
The pupa is enclosed in a slight cocoon about one inch below the surface of the earth.
The perfect insect appears from October till April. It is very common in most situations where its food-plant is found and, owing to its pale colour, is readily seen when flying in the evening twilight. Specimens may also be taken in the daytime resting with outspread wings on the trunks of trees and on fences, where they are much more easily detected than many other species.
Mr. Meyrick thinks that this insect will also be found in Australia.
"Face smooth. Antennæ in [M] bi-pectinated, apex simple. Palpi loosely scaled. Fore-wings with areole simple. Hind-wings with vein 8 anastomosing with cell to beyond middle."--(Meyrick.) (Plate II., fig. 13, head of _V. verriculata_; figs. 25 and 26, neuration of _V. undosata_.)
We have three species represented in New Zealand.
(_Cidaria verriculata_, Feld. cxxxi. 20. _Panopæa verriculata_, Meyr., Trans. N. Z. Inst. xvi. 62. _Pancyma verriculata_, ib. xviii. 184.)
This remarkable species has occurred at Wellington in the North Island, and in the South Island at Christchurch, Ashburton, Dunedin and West Plains.
The expansion of the wings is about 1½ inches. _All the wings are pale yellowish-brown, with many straight oblique parallel dull brown lines; on the fore-wings there are three lines broader and more isolated than the rest, running from the apex to the dorsum_; on the hind-wings the lines near the middle are rather thicker than the others, and have a broad space on each side of them; _all the lines are clearly marked on the abdomen, so that each line appears to be continuous from one side of the moth to the other_.
The perfect insect appears from October till May, and frequents the Cabbage Tree Palm (_Cordyline_), on which its larva probably feeds. According to Mr. Fereday the moth always rests on the dead leaves of the plant, keeping its wings in such a position that the lines are continuous with the parallel veins of the dead leaf, which they precisely resemble in appearance. We have, I think, in this species a most instructive instance of special adaptation to surrounding conditions; and the action of natural selection, in preserving favourable variations of colour and habit, appears to be here unmistakably indicated. Had our investigations been confined to the examination of cabinet specimens only, we might { 54}have long remained in the dark as to the explanation of such an unusual type of wing-marking.