254 AMERICAN COLEOPTERA. 



Linell, except that none of the fifteen specimens which I have ex- 

 amined, have a smooth space on the vertex, which is nearly as 

 coarsely punctured as the head in front. One specimen only has 

 the vertex more feebly punctured, and it is possible that this is 

 variable in the Mexican species also and that the two will prove on 

 comparison to be the same. 



BOIiBOCEROSOMA d gen. 



Eyes completely divided, intermediate intercoxal process between 

 the coxae with a tooth-like elevation, intermediate coxse very nar- 

 rowly separated, nearly contiguous. Other characters as in Bolbo- 

 ceras. 



Type. — Scarahceue Jarctus Fab. 



Bolbocerosoma farctum Fab. 



In this well known and widely distributed species the number of 

 strise differ. Those in which the second and fifth stride are absent 

 or partly indicated are farctum Fab., those with seven entire strise 

 are tumefactum Beauv. Intermediate specimens occur and it is 

 therefore hardly necessary to retain the latter name, as there is 

 otlierwise no difference between the two forms. 



Cautliou humectiis Say (indigaceus Lee). 



In Henshaw's " Third Supplement to the Coleoptera of America 

 North of Mexico," humectas is given as an additional species, but is 

 according to Dr. Horn,* the same as indigaceus Lee. 



Copris arizoiiensis n. sp. — Form of mac/ios and remotns but larger. The 

 male has the clypeus broadly emarginate, head in front coarsely punctate, behind 

 smooth, frontal horn slightly arcuate. Thorax with a narrower median protub- 

 erance than in remotus or machus, which is at apex triangularly emarginate with 

 the angles rounded, the latter straight, not divergent, surface of the protuber- 

 ance slightly flattened, without longitudinal median impression, on each side 

 near side margin a born-like straight projection, the surface between these and 

 the median protuberance deeply excavated and coarsely but rather sparsely 

 punctate, between the usual short carina near side margin and the horn is at 

 about middle a shallow fovea, which is coarsely punctured, surface of thorax 

 coarsely punctured, densely at sides, more finely and sparsely punctured at mid- 

 dle of the disk ; side margin of thorax oblique in front, front angles acute, hind 

 angles broadly rounded. 



The female has the clypeus triangularly emarginate, the frontal horn is shorter, 

 dilated at apex and feebly emarginate, the median protuberance of thorax is 

 broadly rounded in front, with a slight median impression at apex, the projec- 



» See Bates, Biol. Cent. Am., vol. ii, pt. 2, pp. 385 and 386. 



