The caterpillar is extremely variable, the colouring of different individuals being apparently much influenced by their surroundings; those specimens, for instance, taken from the pale green foliage of the mahoe (_M. ramiflorus_) resemble in colour the twigs of that plant, while others captured feeding on the white rata (_Metrosideros scandens_) are dark reddish brown. Fig. 8b is drawn from a larva found on the fuchsia, which, when in its favourite position, viz., sticking straight out from the side of a branch, is so much like one of the sprouting twigs that it absolutely defies detection. When full-grown this insect buries itself about two inches in the earth, where it shortly becomes a dark chestnut-brown pupa, lighter between the segments. The time required for the development of the perfect insect depends upon the season, larvæ which undergo their transformations in the spring developing much more rapidly than those that feed up in the autumn.[18] This insect is extremely variable, having been formerly divided into several distinct species; the two most usual forms are those shown at Figs. 8 and 8a, but every intermediate variety exists. The sexes are distinguished by the usual differences in the antennæ. My experience leads me to believe that the light varieties occur more frequently in the female than in the male sex, and also that the dark larvæ give rise to dark moths, and _vice versâ_, although a great many more specimens will have to be reared before these can be regarded as established facts. {89}Family GEOMETRIDÆ. _Selidosema panagrata_ (Plate XI., fig. 7 [M], 7a [F], 7b larva). One of our commonest moths, occurring in great numbers in the forest throughout the whole summer.