192 INSECT ARCHITECTURE. 



A wood-boring caterpillar, of a species of moth 

 much rarer than the preceding (JEgeria asiliformis, 

 Stephens), exhibits great ingenuity in construct- 

 ing a cell for its metamorphosis. We observed 

 above a dozen of them during this summer (1829) 

 in the trunk of a poplar, one side of which had 

 been stripped of its bark. It was this portion of 

 the trunk which all the caterpillars selected for 

 their final retreat, not one having been observed 

 where the tree was covered with bark. The inge- 

 nuity of the little architect consisted in scooping its 

 cell almost to the very surface of the wood, leaving 

 only an exterior covering of unbroken wood, as thin 

 as writing paper. Previous, therefore, to the chry- 

 salis making its way through this feeble barrier, it 

 could not have been suspected that an insect was 

 lodged under the smooth wood. We observed more 

 than one of these in the act of breaking through this 

 covering, within which there is besides a round move- 

 able lid of a sort of brown wax*. 



Another architect caterpillar, frequently to be met 

 with in July on the leaves of the willow and the 

 poplar, is, in the fly state, called the Puss-Moth 

 (Centra vimda). The caterpillar is produced from 

 brown-coloured shining eggs, about the size of a 

 pin's head, which are deposited — one, two, or 

 more together — on the upper surface of a leaf. 

 In the course of six or eight weeks (during which 

 time it casts its skin thrice) it arrives at its full 



Eggs of the Puss- Moth, 



* J,R. 



