6 PROCEEDINGS OF THE NATIONAL MUSEUM vol. lu 



In the present study we have examined Ontho'phagus from every 

 state in the United States except Washington, Oregon, California, 

 and Nevada. A fossil species, however, has been described from 

 California. Pierce (1946) described Onthophagus everestae on the 

 basis of a head and front tibia fomid in the La Brea tar pits. 



The original description follows: 



Genre. Onthophage; onthophagus. Dernier article des palpes maxillaires 

 ovalaire. Palpes labiaux terminus par des articles qui paroissent plus grands 

 et qui sont trfeh^riss6s de poils. 



Corps presque rond, un peu deprim^. Chaperon demicirculaire, alonge" 

 Corselet trfes grand, se rapprochant de la figure circulaire, enchancr6 en devant' 

 Pattes des bousiers. 



Exemple. Copris taiirus Oliv. 



Adults.^ — -In the United States and Canada the beetles of the genus 

 Ontho'phagus are small to moderate in size, 2.8 to 14.0 mm. in length, 

 oblong oval, with a short thick compact body, convex above and 

 below, with middle legs far apart and hind legs far back. Males 

 usually have the head horned or tuberculate and (or) the pronotum 

 with horns or other protuberances; females have the head carmate 

 and sometimes the pronotmu with a carina or other minor elevation. 



Mentum hairy, transverse, quadrangular, emarginate; labial palpi 

 haii'y, 3-segmented, the first segment slightly shorter than the second, 

 the thu-d very small and inconspicuous, the fii'st segment obovate in 

 profile and abruptly produced on the upper side while the second is 

 securiform and obhquely truncate. Labrmn membranous, densely 

 cihate, concealed by the clj^peus. Mandibles elongate, rounded, 

 without teeth, membranous toward apex, and cihated on internal 

 edge. Maxillae terminating in a large membranous cihated lobe, 

 palpi 4-segmented, the first segment short and slender, the second and 

 third short and more robust, the fourth fusiform and truncate at the 

 end. Clypeus relatively smooth in the male, carinate in the female, 

 varible in shape. Antennae 9-segmented, with a densely, finely pu- 

 bescent 3-segmented club. Pronotum large, convex, rounded do\vn- 

 ward at sides. No visible scutellum. Elytra short, a Uttle convex, 

 somewhat narrowed and rounded posteriorly; seven striae. Legs 

 moderate; the anterior tibiae quadridentate, sometimes slender and 

 elongate in males, with tarsi present in both sexes; middle and pos- 

 terior tibiae apically enlarged and truncate; tarsi slender, cihated on 

 inner edge, the first segment elongate and subparallel; claws small. 

 Metasternum long and somewhat parallel-sided, separated from the 

 very short mesosternum by a rectilinear groove. Pygidium exposed. 

 Males with last abdominal segment broadly emarginate at middle; 

 females with last segment not constricted at middle, practically 

 uniform in length. 



