274 COLEOPTERA OF NORTH AMERICA. 



The narrow epipleural margin is striate transversely, and stri- 

 dulation is produced by rubbing against this surface the sharp 

 edge of the hind femora, which are flattened and sulcate beneath. 

 The legs are slender, compressed, and punctate. 



The sexual characters are obvious in the antennae, heavy in 

 tlie I, slender in the ?. In some of the species the abdomen 

 in the last-named sex is enlarged, and the intercoxal process is 

 so broad as to show that the character possesses not even a 

 generic value; tlie division Prioni subterranei of Lacordaire has 

 tlierefore no foundation in nature, and its contents should be 

 distributed according to the affinities of the individual genera. 

 The 5th ventral segment in the % is truncate and broadly emar- 

 ginate, so that the Gth is visible ; in the 9 it is more elongate, 

 gradually narrowed behind and truncate, and the Gth segment is 

 not exposed. 



Our genera arc but two in num])cr, Prionus, containing several 

 species, occurs in every part of tlie country; Ilomaesthesis (P. 

 integer Lee, einarginatus Say) found in Colorado and New 

 Mexico. F. innocuaa Lee, is the female of one of these species, 

 probably emarginata ; the hind coxa3 are very widely separated, 

 and the intercoxal process of the 1st ventral segment is very 

 short and wide. 



There is much difference in the soles of the hind tarsi, which 

 sometimes, as in F. brevicornis, are as thickly clothed with hair 

 as the other feet and marked with a narrow medial groove; some- 

 times, as in F. palparis and Homsesthesis, flattened or broadly 

 concave and nearly naked ; sometimes again, as in F. fissicornis 

 and imbricornU, the covering of hair is thin, so that the joints 

 appear ])unctured, with a narrow smooth medial groove. 



We see, therefore, in this genus that structural characters 

 assume a merely specific importance, a fact which must be con- 

 stantly borne in mind in attempting a rational classification of 

 Cerambycidye. 



Tribe V.— TRAG®SOMIIVI. 



This tribe is represented in our founa by Tragosoma Harrisii, 

 which scarcely differs from the North European T. depnarium ; 

 it occurs from Newfoundland to Vancouver Island, but is not 

 abundant. The body is elongate (30-35 mm. long) ; the prothorax 



