Species of Butterjiy from Mexico. 39 



merable nests, inclosed apparently in white paper bags, in the man- 

 ner of bunches of grapes in England to preserve them from birds 

 and flies. I had the curiosity to examine one of these, which I found 

 to contain numberless caterpillars. The texture is so strong that it 

 is not easily torn, and the interior contained a quantity of green leaves 

 to support the numerous progeny within." Respecting this state- 

 ment, it is however to be observed, that the white paper bag did 

 not, in the specimen under examination, inclose, but on the contrary 

 formed the nest itself. Moreover, when we consider the " number- 

 less caterpillars " which one of these nests must contain, and their 

 amazing voracity, it will be at once perceived that the few leaves 

 attached to the sprig inclosed within the nest cannot be sufficient 

 support for the numerous progeny within, but tliat on the contrary 

 each of them must be under the necessity of making constant ex- 

 cursions for the purpose of feeding. And when we further consider 

 that from the firmness of the texture of the nest it has in all proba- 

 bility formed the habitation of the entire brood from the time of their 

 first exclusion from the e^g, instead of being abandoned and a fresh 

 nest formed in a more commodious situation, for the supj^ly of the 

 inhabitants when the immediately adjacent stock of food has been 

 consumed, (as is the case with those social caterpillars which merely 

 form slight webs for their habitations,) the instinctive knowledge of 

 the caterpillars becomes evident, as, by the time that they are full- 

 fed, they must be under the necessity of travelling to a considerable 

 distance from their habitation for fresh food ; and were it not for 

 this faculty they would not be able to retrace their steps to the 

 nests. Reaumur, indeed, asserts that the larvae of Eriogaster la- 

 nestris, which live in society, pave their passages with silk, in order 

 to render them more easy for the insects to walk upon ; but in the 

 ' Insect Architecture' it is more broadly stated that "no individual in 

 these communities moves an inch without constructing such a path- 

 way both for the use of his companions and to facilitate his own re- 

 turn." As, however, this idea is clearly generalized from Reaumur, 

 and as the insect instanced by the latter is eminently a silk-weaving 

 insect, it is not improbable that in other instances (especially as in 

 the present,) where the larvae are not general spinners, the return of 

 the larva to the nest is eifected by the possession of the same in- 

 stinct as that which directs the bee when at a surprising distance to 

 her hive, and which appears to me to result neither from extensive 

 powers of vision, as some authors have endeavoured to prove, nor 

 from the operation of memor}^, as supposed by Rogers in his ' Plea- 

 sures of Memory'*. 



* Hark ! the bee winds her small but mellow horn, 



Blithe to salute the sunny smile of morn; O'er 



