88 COLEOPTERA OF NORTH AMERICA. 



in two foreign species of Nemosoma. The anterior coxae are 

 entirely enclosed. 



Eyes rounded. Nemosoma. 



Eyes transverse ; 



Ligula bilobed, tibiae not spinous, anterior angles of thorax not prominent. 



Temnochila. 

 Ligula bilobed, tibiae spinous. Alindria. 



Ligula entire, tibiae not spinous, anterior angles of thorax prominent. 



Trogosita. 



Trogosita and Temnochila are represented on both sides of the 

 continent ; the other two genera only in the Atlantic district. 



Sub-Family II.— PELTIBAE. 



Oval, flattened, or rounded convex insects, having always a 

 flattened margin; the front is truncate; the last three joints of 

 the antennae form a loose perfoliate club. The anterior coxal 

 cavities are open behind, except in Nosodes. 



Mentum transverse, emarginate ; antennal grooves feeble ; 



Anterior coxal cavities closed ; tibiae without terminal hooks. Nosodes. 

 Anterior coxal cavities open ; anterior tibiae with a terminal hook. 



Peltis. 

 Mentum minute, oval ; antennal grooves deep ; 

 Anterior coxal cavities widely open ; tibiae without terminal hooks. 



Thymalus. 



The species of the first and second genera are flattened ; the 

 elytra are striate, with square punctures, in the first tuberculate, 

 in the second with the sides of the body serrate ; the third genus 

 is convex, with the elytra irregularly punctured. 



Sub-Family III.— PELTASTICLDAE. 



Peliastica tuberculata Mann., a small oval pale-brown insect 

 found in Russian America, presents so many anomalies, that it is 

 doubtful to what family it properly appertains. I have placed it 

 in the present, as a sub-family in preference to establishing for it 

 a separate family ; which is, indeed, the only other course prac- 

 ticable, unless it be received as a sub-family of Silphidae. 



The form is oval, with depressed margins, like a miniature Pel- 

 tis. The body is coarsely punctured, aud the elytra are marked 

 with four rows of small black tubercles, separated by pale spots. 



