96 Zoologica: N. Y. Zoological Society [HI; 3 



c/woa among the Heteromera. Hamilton (1886) long ago noticed 

 the resemblance of the larval Cucujus clavipes to the Pyrochroid 

 Dendroides canadensis larva. As show^n in his very valuable 

 paper on the larvze of Coccidotroplivs and other genera (Zoo- 

 logica III, No. 7) Boving divides the Cucujidae auctorum into 

 four families, the Silvanidse, Cucujidse {sens, str.), Lgemophlceidse 

 and ScalariidiE. The last of these he relegates to the group 

 Cleroidea, and states that they are closely connected with the 

 family Bothioderidse of Craighead (1920). 



Apart from several species of considerable economic im- 

 portance, the little that is know^n concerning the habits of these 

 four families of beetles is scattered through the literature. Such 

 data as I have been able to glean in regard to the European, 

 North American and cosmopolitan species have been brought to- 

 gether in condensed form in Zoologica III, No. 5. From these data 

 it will be seen that the Cucujids, taken as a whole, exhibit certain 

 tendencies which are not without significance in connection with 

 the peculiar behavior of Coccidotrophus and Eunausibius. If we 

 exclude the Scalariidse, which Fiske (1905) has shown to be 

 parasitic in their larval stages — resembling in this respect the 

 Bothrioderidse — we notice that the various genera and many of 

 the species of the remaining families show an extraordinary 

 diversity, one might say versatility of behavior. They occur in 

 a great variety of habitats such as stored human foods of vege- 

 table origin, under bark, in decaying wood, in the burrows of 

 bark-beetles, under dead leaves and rubbish, and feed on all 

 sorts of substances mainly of a vegetable and especially of a 

 concentrated or highly nutritious character. Many of the spe- 

 cies are scavengers, others are undoubtedly predaceous and prey 

 on the larvae of other insects. The adult beetles seem to be 

 rather long-lived and usually, if not always, live gregariously 

 with their larvse, all the active stages feeding on the same sub- 

 stances. The developmental period is certainly very brief in 

 some species, as e.g. in Cathartns advena, the whole life-cycle 

 of which, from the egg to the imago may require only three weeks 

 and in the saw-toothed grain beetle (Onjziephilus surinamensis) 

 less than a month. As a rule both the beetles and the larvse of 

 the vegetarian and detritivorous species are very tolerant of the 

 presence of other insects and actually seem to seek their compan- 



