THE DESEET CORTST FLEA-BEETLE. 17 



possible that it is occasionally picked" up by birds, yet no definite 

 observations have ever been made upon this, and the Bureau of 

 Biological Sui'vey has no records bearing upon this species, though 

 related species have been found to be taken as food by certain birds. 



PREDACIOUS ENEMIES. 



The larvae of this beetle are without doubt fed upon by several 

 subterranean larvae of ground beetles which have been found to 

 inhabit the soil in the vicinity of corn plants. The adults are preyed 

 upon by the nymphs and adults of Reduviolus ferus L. Mr. Wilson 

 first took specimens of these nymphs, which be found feeding upon 

 Chaetocnema adults, at Tempe, Ariz., and reared them to maturity, and 

 then found that both adults and nymphs were feeding upon the flea- 

 beetles. It is quite likely that other reduviids also attack this species. 



At Holtville, Cal., the writer found a great many beetles with their 

 bodies almost covered by a species of mite. Upon being sent to 

 Washington these mites 

 were determined by Mr. 

 Nathan Banks as Pedicu- 

 loides sp. They have since 

 been found quite frequently 

 upon adult flea-beetles. 



PARASITIC ENEMIES. 



During his observations 

 in 1915,^ the writer discov- 

 ered that a small parasitic 

 wasp, Neurepyris sp.^ (fig. 

 7), was prejdng upon the 



1 i- J.1, • FiG- 7. — Neurepyris sp., a parasite of the desert corn flear 



arvae and prepupae of this ^^^^j^ Greatly enlarged. (Original.) 



flea-beetle. Six specimens 



taken in the soil, already within the pupal cases, were each found to 

 have very small, insignificant external larvae feeding upon them, the 

 larvae being attached to the ventral side just back of the hind pair of 

 legs. These were carefully placed in small vials, and subsequently 

 several of the parasites died, while one specimen pupated and finally 

 changed to an adult, the hymenopterous larva? in the meantime 

 having completely consumed the beetle larvae. 



Th(^ a(]ult of this parasite is very small, black, with yellow legs, 

 and its papal case, which is about the aizo of a Chaetocnema pupa, 

 is constructed in the soil of a brown, densely woven material. The 

 lurvfi] stage of this parasite was found to be about 8 days and the 

 pupal stage 24 days. This was (hii-ing tlu; montli of May, with the 

 mean temperature about 76° F, 



' At Tnmpc, Ariz. ' I)<"icniiiii''il liy Mr. S. A. Kohwor. 



