514 COLEOPTERA OF NORTH AMERICA. 



rounded, not convex, finely granulated in our species. Antennas 

 with large scape (elongated and curved in some foreign genera), 

 and large compressed solid club, which is pubescent except for a 

 small space at the base; funicle composed of four small joints. 

 Prothorax elongate, truncate before and bisinuate behind ; sub- 

 sinuate on the sides ; flanks broadly excavated for reception of 

 front legs. Prosternum moderately long in front in the coxae, 

 which are very large, conical, exserted, and contiguous in our 

 species; space behind the coxas very short. Pronotum consider- 

 ably longer than the under surface ; middle of base notched for 

 reception of the carina of the inesonotum. Mesosternum trian- 

 gular, middle coxse narrowly separated ; episterna veiy large, 

 quadrate, occupying the space formed by the prolongation of the 

 pronotum ; epiniera small, transverse, posterior, and indistinct. 

 Metasternum very long, episterna parallel, rather wide ; hind 

 coxse slightly separated. Ventral segments five; first and second 

 very short, together scarcely equal to the third, which is equal to 

 the fourth; fifth a little longer, rounded .behind; last dorsal seg- 

 ment horizontal, partiallj^ or completely covered by the elytra, 

 according as the segments are deflexed or retracted. 



Elytra margined and perpendicularly declivous at base, striate, 

 variously prolonged into processes at tip, according to species 

 and sex. Mesonotum strongly carinate. 



Legs short, thighs stout, compressed; tibiae shorter than the 

 thighs, stout, unguiculate, marked on the outer side with trans- 

 verse ridges. Tarsi long, slender, first joint as long or longer 

 than the three following united ; fourth joint one-half as long as 

 the third ; fifth as long as the joints 2-4 united ; claws long, 

 simple, divergent. 



This sub-family is represented in our fauna by a few^ species of 

 Platypus found chiefly in the Southern States. The species are 

 cylindrical, and suggest a resemblance to certain Colydiidse, from 

 which, however, they widely depart in structural characters. 



Platypus is represented by a few species on each side of the 

 continent. 



Sub-Family II.— SCOLYTIN^. 



The characters by which this sub-family differs from the Platy- 

 podina3 have been alreadly sufficiently pointed out ; in other re- 

 spects the species differ greatly according to genus and tribe, and 



