CERAMBYCIDAE. 285 



ternally, but the aflQiiities seem to be stronger than with any other 

 group. The type and only species is Caliidium acxj'asciutum 

 iSay, a rare insect of the Mississippi Valley. 



Haplidus is founded upon H. tcstaceus Lee, a slender finely 

 pubescent brown insect, without any striking characters; it occurs 

 in California and Utah, and the affinities of it seem to us also 

 doubtful. 



Sub-Gronp 2. — A cheysones. 



Slender, sub-cylindrical species, with slightly dilated palpi ; 

 the head short, and front perpendicular as in Oemes; the front 

 coxa3 globose, prominent (contiguous in Achryson), not angulated 

 externally, trochantin not visible ; the middle coxa3 are also 

 prominent, closed externally, tlie mesosternum is moderately wide, 

 truncate at tip in A. siwinanium, narrow and sub-triangular in 

 the Texan A. coticolor; the elytra are armed with a terminal 

 spine in the former, but are rounded in the latter. The 5th ven- 

 tral segment of % is truncate, but not shorter than the 4th. 



A. .^urinamvm (Linn.), (Stenocorus circuviflea-us Fabr.) is 

 found from the Middle States to Mexico and South America; it 

 is a slender pale-brown insect, with dark angulated lines on the 

 elytra. 



Sul)-Group 3. — a K A 1 1, 1 ^ . 



Ycry small slender species of piceous color, very finely punc- 

 tured and pubescent, constitute this sub-group. The head is 

 short, as in the other sub-groups, the i)alpi very unequal, the 

 labial short, the maxillary long with the last joint triangular, 

 obliquely truncate so as to appear pointed ; eyes large, coarsely 

 granulated, deeply emarginate, almost divided; front coxiB very 

 prominent, nearly contiguous, the prostern'um being narrow, and 

 pointed behind; the coxal cavities are subquadrate; the middle 

 coxa3 are prominent, separated by the triangular mesosternum, 

 the cavities are angulated externally, but the epinujra are very 

 small, and do not fully reach the coxtc; the episterna of the meta- 

 thorax are linear; the 1st ventral segment is somewhat longer 

 than usual. The legs are short, the thighs thick and clavate, 

 the 1st joint of the hind tarsi longer than the 2d and od. 



The mesonotuni is covered with stridulating surface; it is less 

 transverse than usual, nearly quadrate, and finely margined at 

 the sides. 



