28 COLEOPTERA OF NORTH AMERICA. 



sides of the continent. Piplochila (Rembus Latr.) is represented 

 ouly east of the Rocky Mountains, while Picaslus is confined ex- 

 clusively to Eastern North America. The species of the latter are 

 usually large; some are of a beautiful violet color, and in all of 

 them the eighth interval is carinated from the base for at least 

 one-third the length. They are found under stones and pieces of 

 wood, and are more numerous in the Southern States. 



Tribe X.— CHI^NIINI. 



The ligula is free at the apex, with distinct paraglossse ; the 

 labrum is fiat, rarely deeply emarginate ; the mentum strongly 

 toothed (except in Anomoglossus). The antenna? have three 

 basal joints smooth and glabrous. The anterior tibias are scarcely 

 thickened externally, and but slightly spinous. The anterior tarsi 

 of the male have three (rarely four) joints dilated, square with 

 rounded angles, and covered beneath with a dense brush of hair. 

 The elytra are regularly rounded behind, and not sinuate; the 

 third interval has a single puncture. 



The systematic difference between this tribe and Pterostichini is 

 wholly sexual, yet the genera may be easily recognized, since the 

 Chiasmi are densely pubescent, and the Oodes have the ocellate 

 punctures of the elytra very near the margin, and the eighth and 

 ninth striae confluent, characters not found among the Pterostichini. 



Two groups are contained in this tribe. 



Group I. — Chlaenii. 



Body densely pubescent, outer stria? of the elytra normal. 



These are usually prettily colored metallic species, found under 

 stones and pieces of wood in moist or shady places ; they evolve 

 a strong odor, which recalls that of a mixture of camphor and 

 creasote. 



Mentum not toothed ; labrum deeply emarginate. Anomoglossus. 

 Mentum tooth distinct, emarginate ; 



Last joint of palpi truncate. Chljenips. 



Last joint of palpi oval, nearly pointed. Atranus. 



To Anomoglossus belongs, besides the two species CM. emar- 

 ginatus and CM. pusillus, upon which the genus was founded by 

 Chaudoir, also CM. amcenus Pej. Of these genera, Chiasmus alone 

 is represented in the western part of the continent. 



