148 

 GENERAL NOTES. 



CHRYSOMELID LARV^ IN ANTS' NESTS. 



Mr, T. D. A. Cockerell has, in the July (1891) number of the Entomolo- 

 gist's Monthly Magazine^ an article on two case-bearing Chrysomelid 

 larvae from Colorado, one of them being found in the nests of an ant, 

 " apparently Formica fusca,^^ the other occuring under rocks. Dr. Ham- 

 ilton, to whom specimens of the former larva were submitted by Mr. 

 Cockerell, declares them as " very probably the larva of Coscinoptera 

 vittiger a .,'''' and is inclined to think that their occurrence among ants is 

 merely accidental. It seems that both Br. Hamilton and Mr. Cockerell 

 have overlooked a note which we published in the American Naturalist 

 for 1882, p. 508, where we first called attention to the myrmecophilous 

 habit of the larva of C. dominicana. We had then received numerous 

 specimens of the cases found in Wisconsin in a large ants' nest. Sub- 

 sequently the same cases were found by Mr. Pergande, at Washington, 

 D. C, among the colonies of Camponotus melleus, and last year we 

 received from Mr. H. G. Hubbard another large lot of the same cases, 

 found at Helena, Mont., in the hills of Formica obscuripes. In all these 

 instances we vsucceeded in breeding the imago, which proved to be C. 

 dominicana, and from our experience it seems safe to say that the oc- 

 currence among ants of this Chrysomelid larva is not accidental, but 

 rather normal. This does not imply, however, that larvae do not feed 

 on old leaves remote from ants' nests, since in our account of the trans- 

 formations of the species (Sixth Rep. Ins. Mo., p. 127) we have shown 

 that it does. Whether or not Mr. Cockerell's species from Colorado is 

 C. vittigera it is not possible to tell without having bred the imago. His 

 short description of the case and the larva agrees very well with G. 

 dominicana as described and figured in our Sixth Missouri Report. 

 Still it is possible that the cases and larvae of the two species resemble 

 each other so closely that they can be distinguished only upon careful 

 comparison. 



The larvae of two European species of Clythra are known to live with 

 ants, and some years ago we received from Mr. H. K. Morrison cases 

 of a Chrysomelid found in an ant's nest in Arizona. These evidently 

 belong to the Clythrini, but are specifically if not generically different 

 from Coscinoptera dominicana. From these records, few as they are 

 in comparison with the large number of species the habits of which are 

 still unknown, it is safe to say that at least some species of the tribe 

 Clythrini must be considered as myrmecophilous in the larva state. 



That in the case-bearing Chrysomelid larvae the case serves as a pro- 

 tection from enemies there can be do doubt; but if Mr. Cockerell says 

 that the case-making habit in Coscinoptera may have been acquired as 

 a protection against the bite of the ants, he forgets that many other 

 soft-bodied and quite unprotected insects live peacefully in company 



