RHYNCHITIDAE. 429 



front for the protection of the legs; coxal cavities approxi- 

 mate, except in Pterocolus. 



Mctasterniini rather long, with narrow side pieces; shorter 

 with Avidc side pieces in Pterocolus, 



Elytra separately rounded behind, exposing the pygidium 

 in some genera; conjointly rounded, and covering the ]'3'gi- 

 dium in others, epipleura; distinct; submarginal fold on inner 

 face short and straight. 



Abdomen with five free ventral segments, nearly equal 

 in length, separated by straight sutures, intercoxal process 

 acute except in Pterocolus; % without additional anal seg- 

 ment, pygidium in both sexes triangular, deflexed; sides of 

 segments not forming an acute edge, and not fitting into a 

 lateral groove of the elytra. 



Anterior coxai usually conical, contiguous, and prominent; 

 smaller, rounded and separated in Pterocolus. 



Middle coxas similar to the front ones. 



Hind coxge transverse, reaching to the margin of the 

 elytra, or nearly so. 



Legs slender, rather long, tibia3 truncate at tip, with small 

 terminal spurs; tarsi brush-like beneath, 4-jointed, third 

 joint broad deeply bilobed; claws bifid, or acutely toothed. 



Thouo-h nearly related to the preceding famil}^ tljese species 

 are reachly distinguished by the absence of labruni, and the 

 pecuHar form of niaiidible, which recurs again only in Desmoria, 

 an Erirhine genus of Curculionidaj. 



While in Rliinomacerida) a relationship to normal Coleoptera 

 is seen in the presence of a Inbruni, and better development of 

 maxillary palpi, a similar tendency is evinced in the Rhynehitidie 

 by the distinct e])ii)leura!. In tlic anomalous genus Pterocolus 

 moreover, tlie protliorax is distinctly and acutely margined at the 

 sides, and excavated beneath, so as to form a large cavity for the 

 reception of the front and middle legs. This character is seen 

 in no other Khynchophorous insect in our fauna, and would 

 almost warrant its reception as a distinct family. For the })res- 

 eiit, however, we prefer placing it as a sub-family. 



Sub-Family I.— RHYNCIIITIN.E. 



The distinctive characters of this sub-family have been pointed 

 out, but may be briefly resumed as follows: — 



