COLYDIIDAE. 91 



genera, except Oxyla?mus. iu which also the anterior coxal cavi- 

 ties are open behind. 



A. Frontal margin broad, covering the insertion of the antennae ; 



Club of antenna? 3-jointed ; (thorax with impressed lines) ; 



Anterior tibia? with one spur enlarged, hooked ; elytra finely or 

 scarcely striate. Aulonium. 



Anterior tibia? with small spurs ; elytra ribbed. Colydium. 



Club of antennae 2-jointed ; body costate. Eulachus. 



B. Frontal margin not dilated ; base of antennas exposed ; 



Anterior coxa? distant ; 

 Eyes flat ; spurs of the tibia? small, outer angle prolonged ; (elytra 

 striate, body very elongate). Nejiatidium 



Anterior coxa? contiguous ; 



First joint of tarsi long ; club of antenna? with two distinct joints ; 



(elytra costate). Pleukidium. 



First joint of tarsi short ; club of antenna? globular, composed of 

 two connate joints ; elytra coarsely punctured in rows. 



Oxyl^emus. 



Tribe III— BOTHRIDERI1VI. 



In this tribe the posterior coxa3 are widely separated, and the 

 first ventral segment is elongated. The species are somewhat 

 flattened, and the elytra are ribbed ; the buccal cavity is deep, 

 and the oral organs are retracted ; the mentum is transverse and 

 concave, and the inferior margin of the mandibles is dilated at 

 the base ; the eyes are not prominent ; the antenna? are short, 

 11-jointed, with the club 2-jointed. 



Two species of Bothrideres are known to me. The genus is 

 distinguished by the anterior coxa? being very widely separated. 



Tribe IV.— PYCBfOMERiari. 



Elongate, somewhat flattened species, covered with coarse punc- 

 tures, having on the elytra rows of very large punctures. The 

 palpi are cylindrical, and the posterior coxa?, as in the preceding 

 tribe, are distant, but the ventral segments are equal in length. 



Antenna? with eleven distinct joints, club 2-jointed. Exdectus. 



Antenna? with ten apparent joints, club solid. Pyc.nomerus. 



Endectus contains Lyctus hsematodes Fabr. and L. reflexus 

 Say, previously enrolled in Pycnomerus, and one nondescript ; of 

 the latter genus but one species is known to me. They are all 

 from the Atlantic States. 



