LeConte.] 



SCOLYTID.E. 341 



Beak thick, neither dilated at tip, nor cylin- 

 drical, slightly narrowed from the base 



to the tip, convex 2. 



Beak very short, parallel on the sides 4. 



" longer, gula only feebly concave trans- 

 versely PHLCEOPHAGUS. 



2. Club rounded, pubescent, feebly annulated 3. 

 Club corneous, truncate at tip, which is 



spongy ; funicle 5-jointed "WOLL ASTONI A. 



3. Funicle 5 jointed AM AURORHINUS. 



" 6-jointed HEXARTHRUM. 



" 7-jointed ELASSOPTES. 



4. Tarsi dilated, antennal grooves long RHYNCOLUS. 



" narrow, antennal grooves very short. . STENOSCELIS. 



The genera and species are fully described by Dr. Horn in the memoir 

 above cited, and need no farther mention at present. 



Family IX. SCOLYTIDaE. 



Mentum moderate in size, varjMng in form in some genera according to 

 sex; without gular peduncle (except in Hylastes, where it is very small) ; 

 ligula and palpi small, the former sometimes retracted, sometimes promi- 

 nent. 



MaxilUie exposed, palpi stout and short. 



Mandibles stout, curved, more or less toothed on the inner side. 



Antennai inserted on the sides of the head, batween the eyes and mandi- 

 bles ; composed mostly of scape and club, funicle usually very short, from 

 1- to 7-jointed; club large, solid, annulated, or i-arely (Phlmotribus) lamel- 

 lated; surface of the club more or less sensitive according to genus. 



Head prominent in some tribes, detiexed and protected by the prothorax 

 in others; eyes usually large and transverse; beak never long, frequently 

 so short as to be not apparent. Labruni feebly developed, sometimes visible. 



Prothorax truncate in front, exposing the head, {Platypodidce, Scolytini 

 and Hylurgini), or prominent, convex and rounded (most Tomicini); lat- 

 eral edge not dis'.inct,* and prosternal sutures obliterated; flanks excavated 

 for the partial reception of the front legs in Platypodidw; coxal caviaes 

 usually confluent; separated in a few genera. 



Mesosternum triangular, pointed behind, or slightly truncate, episterna 

 {Platypodidce) excessively large, ascending between the base of the pro- 

 tliorax and elytra with the epimera small, posterior a;ul transverse, or with 

 thii suture very indistinct; coxae rounded, not widely separated. 



Metasteruum long, sometimes, (Platypodidce) very long; side pieces 

 parallel, or nearly so, not dilated in front. 



Legs moderate in length, rather stout, front coxae almost always con- 



*Excopt in S-olytus. Eutomus, as has been elsewhere observed is not a Itliyn- 

 cliopliorous insect but allied to Shipidandriis. 



