170 FREDERICK BLANCHARD. 



is more robust, the elytra more oval, the thorax coarsely punctured, the 

 punctures, however, not closely crowded The thoracic punctuation of 

 the male is very closely crowded. 



Choeridium. — Canthon perplexus Lee, as mentioned by its author 

 although very much smaller, bears a striking resemblance in appearance 

 to Choeridium. This resemblance is further increased by some of the 

 details of structure in the latter genus which may be worthy of mention. 



The male of C. histeroides Web., has the spur of the anterior tibiae 

 dilated in the form of a small circular disc sessile and strongly deflexed, 

 while in the female the spur is slender and more or less acute. The 

 pygidium in the male is less broadly rounded at the tip than in the female 

 and the last ventral is more evidently emarginate. 



In C. LeContei Harold, which Dr. Horn says. Trans, v, 137, differs 

 from C. Msteroides by having the hind angles of the thorax much more 

 broadly rounded and the margin at the angle very feeble and not at all 

 reflexed as in the latter, the spur of the male anterior tibiae is also dilated 

 and deflexed, but is less rounded in front and distinctly produced and 

 angulate exteriorly, and it is very thin and translucent. In some females 

 the spur has been observed to be wider and truncate at apex, while in 

 others it is acute and straight or slightly incurved. It may be remarked 

 here that the anterior spur with age is liable to be more or less worn in 

 all of the Coprini, so that in Canthon, for instance, it would sometimes 

 be impossible to determine the sex from the form of the stump remaining. 



The pygidium in C. LeContei is very evidently more convex, espec- 

 ially in the female, and more inflexed at tip than is normally the case in 

 C- histeroides. 



Our species of Choeridiuun have the propleurae transversely carinate, 

 as in some species of Cmitlioa, and anteriorly concave and abruptly as- 

 cending. 



Although the presence of a propleural carina in certain genera of 

 Coprini seems not to have been considered by systematists of very great 

 importance in classification it is suggested with diffidence owing to lack 

 of knowledge of exotic forms, that it may perhaps afford ^me clew to 

 the inter-relations of those genera. With this in mind it would appear 

 natural to reverse the order given in our lists of the species of Copris, 

 placing Copris proper in which the carina is present next after Choerid- 

 ium and Copris {Piriotus) caroKn'i in which it is absent before Phanaeus 

 which in this respect is similar and which also resembles the latter sub- 

 genus in having the elytra seven-sti'iate. 



