134 ACADEMY OF NATURAL SCIENCES 



Length nearly one-fifth of an inch. 



This species was obtained on the river Platte near the Moun- 

 tains. The punctures are so minute as not to be visible, but 

 with the aid of a strong magnifier. 



3. A. EBENEUS [ebenus]. — Black ; clypeus six-toothed ; inci- 

 sure of the posterior tooth as profound as that of the preceding one. 



Inhabits Missouri. 



Body deep black, immaculate, scabrous, with slightly elevated, 

 very numerous points : clypeus six-toothed ; the two anterior 

 teeth hardly more prominent; the fissure separating the poste- 

 rior tooth more acute, and as profound as that of the preceding 

 tooth : thorax convex ; an obsolete, indented, longitudinal, ob- 

 tuse line towards the base ; posterior edge perceptibly projecting 

 into a slight angle in the middle, lateral edge angulated in the 

 middle, and with irregular denticles behind the middle . elytra 

 with [209] obsolete impunctured striae: anterior tibia with three 

 large teeth. 



Length two-fifths of an inch. 



This species very much resembles the preceding, from which 

 it is, however, distinguishable by its superior magnitude, by the 

 much more numerous small tubercles with which its surface is 

 overspread, and by the much more profound fissure which sepa- 

 rates the two posterior teeth of the clypeus from each other; 

 from this fissure a distinct line passes upwards and intersects a 

 similar transverse line drawn from the inner canthus of the eye, 

 as in many species of this genus. 



SCARAB^US Latr. 



S. TRIDENTATUS. — Clypcus with an elevated tridentate line 

 on the anterior submargin. 



Inhabits Arkansa. 



Body black, punctured: clypeus scabrous; an obsolete elevated 

 abbreviated line in the middle ; an elevated transverse tridentate 

 line on the anterior submargin, confluent each side with the 

 lateral reflected edge; tip much narrowed, emarginate, reflected: 

 thorax, punctures generally difi"used : scutel impunctured : elytra 

 with punctured striae : beneath reddish-brown. 



Length three-fifths of an inch. 



The maxillae of this insect are horny, and dentated at tip, but 



[Vol. III. 



