650 BOSTON JOURNAL 



tlie horn that it possesses is larger than the posterior horn of 

 that insect, with which it corresponds in locality but not in di- 

 rection. [176] 



3. C. QUADRIDENS. — Thorax angulated, four-toothed ; head 

 horned. 



Inhabits Mexico. 



Body blackish-violaceous ; head densely punctured, and with 

 an elongated, recurved, trigonate horn, which is as long as the 

 thorax, punctured and acute ; thorax rugose, angulated ; poste- 

 rior angles compressed, elevated, subacute ; on a line between 

 them are two remote, short, vertical, conic denticulations j ante- 

 rior margin near the middle with two short, vertical, conic den- 

 ticulations separated by a raised line ; elytra with obsolete strise. 



Length seven-tenths of an inch. 



A fine species, not so brilliantly colored as the carnifex Fabr., 

 or even as the triangularis nob., from both of which it is emi- 

 nently distinguished by the thoracic denticulations. 



4. C. PROCIDUA. — Thorax three-horned ; head two-horned. 

 Inhabits Mexico. 



Body black ; head punctured, two-horned ; anterior horn ver- 

 tical or hardly recurved, not as long as the head ; posterior horn 

 very short, inclined; thorax punctured, with three horns, the 

 middle one very obtuse and emargiuate, lateral ones acute, in a 

 transverse line on the anterior submargin ; anterior margins de- 

 clivous ; anterior angles rounded; an impressed, abbreviated, 

 doi'sal line and a lateral indented spot ; posterior disk impunc- 

 tured ; elytra with impressed, punctured striiie ; interstitial spaces 

 convex, impunctured. 



Var. a. Highly polished. 



Length more than three-fifths of an inch. 



The armature of the thorax is very similar to that of C. luna- 

 ris Linn., but it is less robust, and is widely distinguished [177] 

 from that species, by having two horns on the head. The variety 

 resembles C. Amnion Fabr,, anajJi/jitica nob., in the thoracic 

 sculpture. 



[Vol. I. 



