CERAMBYCIDAE. 297 



is also different, there being indications, more or less distinct, of 

 two ivory vittae on each elytron. 



Curious sexual differences appear on the under surfaces of the 

 prothorax in Phymatodes and Callidium; the punctures are 

 coarser and more numerous in $ . 



Xylocrius Lee. is founded upon Callidium Agassizii Lee. 

 (Proc. Acad. Nat. Sci., 1861, 357), a black coarsely punctured 

 species, from California ; it is of more convex form than usual in 

 this group, the antennae are shorter and stouter with joints 3-5 

 equal, the palpi unequal, the prosternum narrow and pointed 

 behind, the mesosternum subtriangular, obtusely truncated and 

 slightly emarginate at tip, the hind coxae not inclosed by the 

 side pieces of metasternum. The scutellum is triangular with 

 curved sides, and the mesonotum, though provided with a medial 

 stridulating surface, is punctured and pubescent at the sides. The 

 hind tarsi are stouter than in the other genera of this group, and 

 the thighs are moderately clubbed. 



Tribe III. CERAMBYCINI. 



A very extensive series, of rather difficult definition, and con- 

 taining a large number of genera, which seem to have been 

 unnecessarily multiplied, on account of the unimportance of the 

 characters used for the definition of the separate groups. As 

 here restricted, the tribe contains all of the groups of Sec- 

 tion A. (Lac. Gen. Col. viii, p. 202), which are represented in 

 our fauna, except Asemini and Obriini; in other words, all 

 genera having the eyes strongly granulated, the front coxa! 

 cavities usually open, the abdomen normal in both sexes, and the 

 antennae with the 2d joint small. 



The ligula is sometimes (Oeme, etc.) corneous, but usually mem- 

 branous, and deeply bilobed ; the scutellura is usually rounded, 

 rarely (Chion) triangular and acute ; the stridulating surface is 

 fine, and covers nearly the whole mesonotum ; the antennae 

 are nearly always long, and without distinct sensitive spaces. 

 The mandibles are acute at tip. The middle coxal cavities are 

 sometimes open, sometimes closed, varying frequently, to an 

 appreciable extent, in the species of the same genus. The elytra, 

 as observed by Lacordaire, are not abbreviated, but they are 

 slightly so in Gracilia manca ; the eyes are not divided in any 



