58 



CEEAMBTCID^. 



Subfamily II. DISTENIIN^. 



Group Disteniides, Lacord. Gen. CoUopt. ix, p. 225 (1869). 

 Tribe Disteniini, Leconte ^ Horn, Classif. Col. N. Amer. p. 307 

 (1883). 



Head elongated, more or less gradually narrowed behind the 

 eyes ; the latter transverse, feebly einarginate or entire ; front 

 vertical and very short, almost limited to the transversely raised 

 antennal supports ; clypeus oblique ; mandibles with truncate or 

 scalpriform apical edge; gala produced anteriorly between the 

 bases of the maxillae so that it forms a distinct mentigerous 

 process ; ligula corneous. Antennte inserted before the eyes, close 

 to the base of the mandibles. Front coxae large, globular, their 

 acetabula usually open behind and, except in Cijrtonops, not 

 angulate on the outer side, the epimera having coalesced with the 

 prosternum to form a suture. Acetabula of middle coxae closed 

 or, exceptionally, open on the outer side. Episterna of metathorax 

 very narrow, gradually attenuated behind. Middle tibi® most 

 frequently with an oblique notch on the lower part of the outer 

 border. Wing-venation of the Lepturine type, always «'ithout a 

 cell in the course of vein A 1. 



The Distenihw, though placed by Lacordaire as a group among 

 the Ceramhycides, were given a prominent position in bis arrange- 

 ment of that subfamily, in which also he included the Lephirince. 

 Leconte & Horn (Classif. Col. jV. America), while retaining them 

 also in the Cerambycince as one of their Lepturoid tribes, have 

 suggested that they are a primitive group, a suggestion arising 

 from a consideration of the structure of Distenia, one of the most 

 specialised of the genera in the group. The relationship between 

 the Disteniino' and the Lepturime is, no doubt, a close one, but the 

 differences between them are at the same time so strong that I 

 find a difficulty in placing them both in the same subfamily, and 

 therefore treat the Disteniince as a subfamily in themselves. The 

 genera are few in number, and, with the exception of Cyrtonops 

 and Dynamostes, are all very closely related. 



Synojjsis of the Genera. 



A. Antennae shorter than the body ; not furnished 



with long- close-lying bans beneath. 



a. Acetabula of front coxa9 angulate outwards, 



open behind Cyrtonops, p. -39. 



b. Acetabula of front coxae rounded, closed 



behind Dynamostes, p. 61. 



B. Antennae as long at least as the body and 



generally much longer ; furnished beneath 

 with very long close-lying hairs, 

 a. Eyes somewhat coarsely facetted ; femora 

 fusiform or subcvlindrical. 



