314 COLEOPTERA OF NORTH AMERICA. 



wi'th the last joint cylindrical and pointed ; and (3) the front 

 tibiae obliquely sulcate on the inner side. One of these characters 

 is occasionally absent, but the other two will then, with the 

 general appearance of the insect, make its affinities unmistakable. 

 To the first character there is no exception in our fauna, and only 

 the Traesisternus group of the other continent; Michthysoma, 

 having the last joint of the palpi triangular, is the only exception 

 in North America to the second character; the third character is 

 lost in some genera of low organization, such as Methia, Dysphaga, 

 etc., which are only feebly differentiated from the Oeme group of 

 Cerambycina?. 



The front is vertical, usually large and flat, rarely shorter and 

 convex ; the eyes are usually finely or moderately finely granu- 

 lated, rarely quite coarsely granulated; emarginated, frequently 

 divided, sometimes (Spalacopsis) with the upper lobe wanting.* 

 The front coxse are rounded, never transverse, the coxal fissure is 

 frequently open, so that the cavity becomes angulated, but this 

 character, as in Cerambycidae, is not of great importance ; they 

 are closed behind in nearly all, widely open in Methiini, with a 

 tendency to become open in Monoharamini. The middle coxae 

 are entirely closed by the sternal pieces in the higher forms, of 

 each series, open to the side pieces in the others, but this character 

 is also of small importance. The metasternum never has scent 

 glands; and the stridulating plate of the mesonotum is always 

 undivided, though frequently narrow. The ventral segments are 

 always 5, and present no remarkable characters. The legs are 

 usually short, sometimes (Monoharamus %, Dorcaschema) long; 

 middle tibiae with a tubercle or sinus on the outer face in most 

 genera; tibial spurs short; ungues either ^I'yariea^e (extending 

 in a plane at right angles to the length of the last joint), or di- 

 ve7'geni (not in the same plane, but forming an angle). This 

 character, first observed by Lacordaire, seems to be of great 

 value; in the true Cerambycidae the claws do not appear to vary 

 to the same extent, but to be slightly movable in nearly all, if 

 not all, the species. 



We would arrange the tribes represented in our fauna into 

 series, as follows : — 



* This cliaracter has been already noticed in the Clytini, group Ana- 

 glypti, V. sup. p. 305. 



