164 INSECT ARCHITECTURE. 



of their bodies which is always enclosed in the case, being 

 soft like a meal-worm, or garden-caterpillar, while the 

 head and shoulders, which are for the most part projected 

 beyond the door- way in search of food, are firm, hard, and 

 consequently less liable to injuiy than the protected portion, 

 should it chance to be exposed. 



We have repeatedly tried experiments with the inha- 

 bitants of those aquatic tents, to ascertain their mode of 

 building. We have deprived them of their little houses, 

 and furnished them with materials for constructing new 

 ones, watching their proceedings from their laying the 

 first stone or shell of the stnicture. They work at the 

 commencement in a very clumsy manner, attaching a great 

 number of chips to whatever materials may be within 

 their reach with loose threads of silk, and many of these 

 they never use at all in their perfect building. They act, 

 indeed, much like an unskilful workman trying his hand 

 before committing himself upon an intended work of diffi- 

 cult execution. Their main intention is, however, to have 

 abundance of materials within reach : for after their 

 dwelling is fairly begun, they shut themselves up in it, 

 and do not again protrude more than half of their body to 

 procure materials ; and even when they have dragged a 

 stone, a shell, or a chip of reed within building reach, they 

 have often to reject it as unfit. (J. R.) 



Carpenter-Caterpillars. 



Insects, though sometimes actuated by an instinct ap- 

 parently blind, unintelligent, or unknown to themselves,- 

 manifest in other instances a remarkable adaptation of 

 means to ends. We have it in our power to exemplify 

 this in a striking manner by the proceedings of the cater- 

 pillai' of a goat-moth (Cossus Ugniperdd) which we kept till 

 it underwent its final change. 



This caterpillar, which abounds in Kent and many other 

 parts of the island, feeds on the wood of willows, oaks, 

 poplars, and other trees, in which it eats extensive 

 galleries; but it is not contented w^ith the protection 



