242 PROCEEDINGS OF THE ACADEMY OP 



Georgia, several specimens. Shorter and more robust than the preceding, 

 and easily distinguished by the difference in sculpture. 



Subgroup IV. DORCATOMATA. 



The body is oval convex, or even globose, capable of being closely contracted. 

 The head when deflesed is received into a deep cavity of the prothorax, aud 

 the mandibles abut against the anterior margin of the metasternum, which ia 

 prolonged between the middle coxa? into a short, broad lobe, nearly truncate 

 in front. The antenna? are received in a sternal cavity between the front coxae, 

 and in the mesosternum, which is deeply buried under the metasternum. The 

 first joini is large and auricnlate, and the last three joints dilated and very 

 large, forming a loose club much longer than the preceding portion. The pro- 

 gternum is very short and broad, and separates widely the front coxa?, which 

 are small, conical and ascend perpendicularly along the sides of the cavity. 

 The middle legs are received in deep excavation.? of the meso- and metaster- 

 num, the tarsi resting in small, deep grooves behind the metasternal lobe, and 

 the knees in subhumeral cavities of the epipleurae. The first ventral segment 

 is deeply excavated each side for the reception of the hind legs ; the knees are 

 not received in epipleural foveas. The ventral segments seem disposed to be- 

 come connate. 



Our genera are but two, distinguished as follows: 



Prosternnm produced behind into two long horns. Dorcatoma. 

 Prosternum broadly truncate behind Ccenocara. 



DORCATOMA Herbst, (emend. Thomson, Skand. Col. i. 90.) 



This genus, as restricted by Thomson, and subsequently by Mulsant and Rey, 

 contains species of oval form, having the eyes slightly emarginated and rather 

 finely granulated. The head is not excavated beneath, but only impressed, 

 and the antenna? are received upon the breast, between the anterior coxa?. 

 Antenna? 10-jointed ; first joint large, auricnlate, second much smaller, di- 

 lated ; 3 7 narrow, very small ; eighth triangular, as long as the six preceding 

 united; ninth triangular, as broad as the eighth in the males, but in the fe- 

 males a little narrower; tenth, oval, about one-third longer than the ninth, 

 more or less curved, rounded at tip. Palpi with the last joint securiform. 

 Prosternum (visible only on dissection) broad, short, concave, produced be- 

 hind into two slender and divergent horns, which fit into excavations of the 

 mesosternum ; anterior coxa? small, perpendicular, widely distant. Mescster- 

 num deeply excavated, concealed under the metasternum, which is produced be- 

 tween the middle coxa?, and truncate in front; medial channel well marked. 

 Feet moderate, tibia? slender, tarsi moderate, first joint somewhat longer. First 

 ventral segment excavated for the reception of hind feet. Elytra generally 

 with two entire marginal stria?, and a short one near the humerus, more or less 

 visible, sometimes with stria? abbreviated near the base. The punctures in our 

 species are arranged so as to leave intervening, narrow, smooth vitta? ; the 

 epipleura? are not at all foveate for the reception of the knees of the hind feel. 



Our two species may be readily distinguished by the sculpture of the elytra. 



Elytra sparsely punctulate in rows, stria? entire setulosum. 



Elytra densely punctulate in bands, striae abbreviated in 



front incomptum. 



1. D. setulosum. ovale convexum nigrum nitidum, pube brevi erecta 

 fusca vestitum, thorace subtiliter punctulnto, elytris subseriatim baud dense 

 punctulatis, seriebus fere per paria approximatis, striis duabus externis pro- 

 fundis, 3ia brevi antennis pedibusque piceo-testaceis. Long. -09. 



Lake Superior, Pennsylvania, G-orgia, also in North Carolina, (Dr. Zimmer- 

 mann.) The punctures of the elytra are fine, not densely placed, arranged al- 

 most in regular rows, which are approximated by pairs ; the pubescence is 



[Oct. 



