276 



punctures throughout the upper-surface smaller and distri- 

 buted over smaller areas. The female differs from the female- 

 of that species in being less convex, with smaller and sparser 

 punctures, sides of prothorax less rounded, and shoulders less 

 produced. From the description and figure of the female of 

 pelorides (the only sex of that species at present described) 

 it differs in having the prothorax nonfoveate and the eyes 

 completely divided by the canthi (so that there is an upper, 

 and an under, one on each side of head), joints of antennae 

 and the tibiae somewhat different. On one (only) of the 

 four males before me there is a small fovea in the exact centre 

 of the forehead. The cusps of the mandibles are placed one 

 above the other, but on one specimen they are represented 

 by feeble swellings only, whilst en another the upper one 

 only is present, but is enlarged and produced upwards as a 

 subcorneal tubercle. The elytra, when quite free from grease, 

 are seen to have very feeble rows of minute punctures, but 

 these are usually concealed ; they have a few fine irregular 

 scratches. 



SCARABAEIDAE. 



BOLBOCERAS. 



The sexes of the larger species of this genus are so 

 strikingly distinct that without certain information it is in- 

 most instances quite impossible to mate them, and to attempt 

 to mate specimens from widely-separated localities (although 

 many of the species are very widely distributed) on mere 

 general resemblance of the non-sexual parts is almost certain 

 to result in error, and has been the cause of several mistakes 

 in the past. Of Blackburn's groups, the first, and the first 

 part of the. second, consist of species whose females are 

 generally very much alike and difficult to distinguish; the 

 second part of the second group contains species whose 

 females are usually quite as distinct (or even more so) than 

 their males; the third group consists of small species without 

 conspicuous horns on either sex; Blackburn remarked of it 

 that there was "either very little external difference between 

 the sexes, or the difference is of a kind that leads to the 

 supposition of the two sexes being distinct species," and he 

 thought it possible that he had described the se^xes of some 

 species as distinct ones. I think it is extremely probable 

 that he and others have done so, and until the sexes can be 

 mated to a certainty it appears to be actually preferable to 

 name the sexes as distinct rather than to incorrectly mate 

 them ; but not being able to confidently mate specimens of 

 even one of many species before me, T prefer to leave the 

 group untouched. 



