240 ceba-MbtcidjE. 



Sifnop^iis of Genera. 



A. Antennfe more or less widely separated at 



base, the head between them either not 

 raised or only slightly raised at the sides. 



a. Head carina'te in front Xylotrechus. p. 241. 



b. Head not carinate in front. 



a'. Lateral margins of elytra straight or 

 nearly straight. 

 a^. First joint of hind tarsi less than 

 twice the length of second and third 



united Clytus, p. 250. 



b'-. First joint of hind tarsi twice as long 



as second and third imited Pkrisscs, p. 254. 



b'. Lateral margins of elytra obliquely in- 

 clined near the base Ischnodora, p. 250. 



B. Antennfe jiot widely separated at tiie base ; 



two subapproximate, divergent elevations 

 on head between them. 



a. First joint of hind tarsi much longer as a 



rule than second and third united. 

 a'. Antennfe not spined. 



a'^. Antennfe ratber closely approximated 

 at base, third joint little or not 

 longer than first ; elytra moderately 



long Caloclytcs, p. 2C0. 



b'^. Antennse less closely approximated 



at base, third joint distinctly longer 



than first ; elytra long and relatively 



narrow. 



a\ Antennae of (S little or not longer 



than body ; episterna of meta- 



thorax with str.aight inner margin. Rhaphuma, p. 271. 

 b^. Antennfe of (5 one-third longer 

 than body ; episterna of meta- 



thorax wath curved inner margin. Clytocera, p. 270. 

 b'. Antennfe spined at apex of one or more 

 of the joints from third to sixth ; the 

 spines sometimes very small and in- 

 conspicuous. 

 «"•'. Third and fourth joints, sometimes 

 also fifth and sixth, spined at tipex, 

 third joint longer than fourth .... Demoxax, p. 280. 

 6^. Third joint only spined at apex ; this 

 joint not longer than fourtli, usually 

 much shorter Psilomerus, p. 209. 



b. First joint of hind tarsi very little or not 



longer than second and third united. 

 a'. Flytra with feeble obtuse elevation at 



base, shoulders not carinate, epipleures 



not widened posteriorly Oligoenoplus, p. 301 



b'. Elytra with short dorsal crest or 



tubercle at base, shoulders carinate, 



epipleures slightly widened posteriorly. Aglaophis, p. 303. 



