BEETLES OF THE GENUS RENOCIS — BLACKMAN 375 



Bemarks.—Csisefs description of the genus Renocis and the species 

 heterodoxus was based upon a single specimen, and this not in perfect 

 condition. This precluded the making of dissections and special 

 mounts of parts that are essential in the proper study of such small 

 insects. For this reason Casey's original description of Renocis may 

 be modified and amplified in several respects. 



On page 257 Casey says, "Anterior coxae in contact with the head 

 beneath ;^prosternum entirely obsolete before them." Dissection dem- 

 onstrates that the presternum is always present (fig. 17, a) though 

 rather narrow, and although it is concealed by the bulbous forecoxae 

 in the entire specimen, its presence may be inferred with certainty 

 by the very evident white setae, arising from the edge of the pro- 

 sternum, which may be seen, even in the type, between the coxae and 

 the head. He also described the teeth on the outer margin of the 

 foretibia as "short, very robust spinules." As shown by figure 18, e, 

 these are neither short nor very robust as compared with those of 

 many other scolytids. Also the antennal club in Renocis heterodoxus 

 only appears to be "longer than the entire preceding portion." 

 Actually it is considerably shorter (fig. 17, A). 



It seems certain that Swaine's genus PseudocryphaUs would not 

 have been proposed had Casey's description been more accurate, for 

 the main characters in which his description differs from that of 

 Casey have to do with the prosternum and the tibial teeth. Indeed, 

 Swaine's description of Pseiidocryphalus applies very closely to the 

 type species of Renocis — much more closely than Casey's description. 

 LeConte's genus Chaetophloeus (figs. 17, q; 18, <?), represented by 

 the single species C. hystrix LeConte, is similar to Renocis in several 

 respects such as body form and proportions, general structure of the 

 frons, antennae, and eyes, and the strongly elevated and crenulate. 

 anterior margins of the elytra. It differs, however, in that the third 

 joint of the tarsus is wider and distinctly emarginate; the pronotum 

 is not strongly deflexed and its anterior margin does not have a 

 fringe of specialized, coarse, erect setae ; and the punctures through- 

 out are coarse, deep, and close and give rise to erect, hairlike setae. 

 The genus Renocis as here constituted includes species that are 

 strikingly different in superficial aspects and that indeed show differ- 

 ences in certain structures that in other groups might warrant includ- 

 ing the species under several different genera. However, a careful 

 study of both entire and dissected specimens shows that in the 

 essential characters mentioned in the revised generic description the 

 necessary uniformity exists. Forms as dissimilar superficially as 

 parkimoniae, penicillatus^ and hraziliensis show all the essential 

 generic characters found in the type species, heterodoxus. 



