286 COLEOPTERA OF NORTH AMEUICA. 



The antennae are hairy, iu % longer, in 9 shorter than the body. 

 Gracilia pygmsea has been introduced in articles of commerce 

 from Europe. G. manca is very rare in the Middle States, and 

 differs by the prothorax being more rounded on the sides, and the 

 elytra a little shorter than the abdomen. 



Group II. — Cerambyci. 



This group contains a large number of genera, which have been 

 partitioned, by Lacordaire into several minor groups, separated by 

 evanescent or variable characters. Although the typical genera 

 of these smaller groups possess in every instance a distinct ap- 

 pearance by which they may be recognized, yet the structural 

 variations observed even within the limits of the genera them- 

 selves, when the species are numerous, are such as to completely 

 jirevent any definition of these minor divisions. For the infor- 

 mation of the general student, we will mention below the groups 

 of Lacordaire to which he has referred, or would refer the genera 

 represented in our fauna. 



We have placed in this group all those genera with coarsely 

 granulated eyes, having the ligula entirely membranous and 

 deeply bilobed, and the middle coxce more or less angulated 

 externally, even when the two sternal plates come into contact. 

 The other characters are all variable to a greater or less degree, 

 as will be seen by the following table. The metathoracic epi- 

 sterna have in many species a distinct aperture near the hind 

 coxa, at the side of the metasternum, which is the orifice of the 

 scent gland, but even in species of the same genus (Elaphidion) 

 they vary greatly in size, so as almost, or even completely, to dis- 

 appear. In the same manner the spines of the antennae, of the 

 femora, and of the elytra have rather specific than generic value. 

 In Eburia there is a gradual transition from those species in 

 which the lateral spines of the prothorax are acute and prominent 

 to those in which they are entirely wanting. 



Antennie 11-jointed, with recurved hooks on joints 3—6 (prothorax plicate, 

 armed, elytra bispinose). Hammaticherus. 



Antennse 12-iointed, sericeous, serrate. Axestinus. 



Antenna? 11-jointed, without recurved hooks ; 



A. Front coxal cavities angulated ; antennne, thighs, and elytra, not 

 spinose ; 

 Frontal suture deep ; metathorax without scent pores ; 

 Prothorax uneven, tubercuhite at the sides. Brothylus. 



