OTIOUIIYNCHIDAE. 457 



4 the mentum is very narrow and tlie other [)art.s of the uiouth 

 very distinctly visible. 



Scythropus occurs on both sides of the continent; the others 

 in the Atlantic region. 



Tribe v.— PROIWECOPI^I. 



Rostrum short, stout, dilated (Coleocenis) or not (Eudiagogus) 

 in front, tip eniarginate. Antennte moderate, scape passing the 

 eyes or not, funicle T-jointed; club oval. Serobes deep, arcuate, 

 confluent or not beneath. Thorax with large lateral lobes, and 

 deeply cmarginate beneath. Scutellura distinct. Abdomen nor- 

 mal. Tibiaj feebly mucronate. Tarsal claws free. 



This tribe, corresponding with that of Lacordaire, may be con- 

 sidered the most sharply defined and natural of the division. Its 

 small and retracted mentum, large thoracic lobes and the deep 

 emarginatiou of the front of the thorax beneath, at once distin- 

 guish it. As in the preceding tribe the gense are entire and the 

 mandibles covered at base. 



Tlie following are the genera in our fauna: — 



Rostrum strongly dilated at tip, scrobes meeting beneath the eyes ; meso- 



.sternum protuberant. Coleocerus. 



Rostrum very feebly dilated, cylindrical flattened, scrobes not meeting 



beneath the eyes, but turning forward ; raesosternum not protuberant ; 



Elytra broadly oval, scutellum small ; metasternum short. 



Aracanthus. 



Elytra oblong, broader at base than the thorax, scutellum transverse ; 



metasternum moderately long. Hudiagogus. 



In the last two genera the articular cavities of the hiiul tibiie 

 are shallow, the outer free edge is, however, double in Eudiagogus. 

 In Coleocerus the hind tibiae are truncate at tip, forming an oval, 

 scaly space, the outer edge of which is formed by a moderately 

 sharp ridge not margined with spinules. The tibiae are feebly 

 mucronate in all of the genera, although the contrary is stated 

 by Lacordaire. 



Coleocerus occurs in Arizona and Texas; Aracanthus from 

 Missouri to Texas; and Eudiagogus from Florida to Texas. 



