1G0 COLEOPTERA OF NORTH AMERICA. 



genera of the first sub-family. I know, however, from observation, 

 that our small species of Eucnemis actually possess this springing 

 power. 



All the species are vegetable feeders ; and the larvae live, some 

 in the earth, others in rotten wood, others prey upon living plants. 



Three sub-families may be defined, as follows : — 



Labrum indistinct ; 



Antennae inserted in grooves ; claws not serrate. EucnemidjE. 



Antennae very approximate ; claws serrate. Cerophytid.<e. 



Labrum distinct. Elatekid2e. 



Sub-Family I.— EUCNEMIDAE. 



The only character separating this from the genuine Elateridae 

 is found in the insertion of the antenna? upon the front, at the 

 inner extremity of transverse grooves, before which the front is 

 expanded again ; the labrum is indistinct ; the prosternum is 

 nearly truncate in front, and the head is always deflexed, and 

 applied to the sternum in repose. 



The species are rare, and are found under bark, or on leaves 

 of plants. Two tribes are indicated : — 



Antennae moderately distant ; maxillary palpi with the last joint acute. 



Mblasini. 

 Antennae approximate ; maxillary palpi with the last joint large, dilated. 



Eucnemini. 

 Tribe I.— JHELASINI. 

 Two genera, of slender form, represented in our Atlantic fauna 

 and in Europe, alone constitute this tribe. They differ in several 

 respects from all other members of the family, and particularly 

 by the large size of the head, so that the eyes are entirely disen- 

 gaged from the thorax ; the mouth is not perfectly applied to the 

 prosternum, as in the next tribe ; the prosternum is truncate in 

 front, and its sutures are parallel, not running to the anterior 

 angles of the thorax, as in the other genera of this sub-family; 

 the middle coxae are small, not angulated externally, and without 

 trochantin ; the epimera are very transverse. 



Tibiae broad, compressed. Melasis. 



Tibiae slender. Tharops. 



Tribe II.— EUCNEMINI. 



Several genera, usually cuneiform, sometimes subcylindrical, 

 and easily recognized by the situation of the antennae in approxi- 



