ENTOMOLOGY, 91 



it bears insulated spines; and not unfrequently it 

 is tubercular. The colour of the kinds that are 

 little exposed, from their situation, to the action of 

 light, is generally yello wish - white ; many of those, 

 however, which are concealed beneath the earth, 

 are light-brown ; most of those belonging to the Lep- 

 idoptera are greenish or brown, sometimes speckled, 

 and occasionally ornamented with golden spots, on 

 which account they were first called Chrysalides and 

 Aureliee. Many pupae have strong angular points 

 projecting from various parts of their bodies, and 

 sometimes these are processes designed for a par- 

 ticular function. Such, for example, are the clavate 

 appendages which project from the sides of the 

 thorax in the pupse of gnats, and some other dipter- 

 ous species which live in the water. The dorsal 

 segments of many are armed with sharp serratures 

 looking towards the anus, which serve an important 

 purpose in their economy, for it is by their means 

 the pupa works its way to the surface of the ground, 

 when the perfect insect is about to be disclosed. 

 When the segments are curved, the convex side, by 

 means of these spines (called adminicvla by Kirby), 

 finds a point d' appui higher up than it occupied 

 formerly, and when it has attained this elevation, 

 another curvature of the abdomen enables it to 

 gain another step. In this way they have no diffi- 

 culty in rising to the surface merely by wriggling 

 the abdomen from side to side. This structure i? 

 well exemplified in the large pupa of the goat moth, a 

 highly magnified view of whose serrated dorsal ridges 



