402 COLEOPTERA OF NORTH AMERICA. 



without trochantio; hind cox^e transverse, nearl)^ contigu- 

 ous, except in Cononotus, where they are very widely sepa- 

 rated ; til)ia3 slender, with the spurs small but distinct; tarsi 

 slender, never lobed, anterior and middle ones 5-jointed, 

 hind ones 4 -join ted; claws simple. 



This family contains a small number of species, mostly confined 

 to northern localities ; those of the first and third tribes live 

 under bark, those of the second are found under stones. 



Our three tribes (or perhaps more properly sub-families) may 

 be separated as follows : — 



Middle coxse with distinct trochantin. Pythiki. 



Middle coxse inclosed by the sterna, without trochantin ; 



Metasternuni short, head not rostrated. Cononotiki. 



Metasteruum long, head with a distinct rostrum. Salpingini. 



Tribe I.— PY'THIIVI. 



Head prominent; last joint of maxillary palpi dilated; mcta- 

 sternum lonp;, body winged; intercoxal process of abdomen small, 

 acute; middle coxa? with distinct trochantin, extending to the 

 epiniera; mandibles visible beyond the labrum, emarginate at tip, 

 and in Priognathus also serrate on the inner edge. 



These species are of moderate or large size, and are found 

 under bark; in general aspect they resemble certain Tenebrio- 

 nidte, but are immediately known by the anterior coxal cavities 

 being open behind. 



Three of our genera, Sphalma, Crymodes, and Priognathus, 

 are peculiar to the northern part of America; the other two are 

 also represented in Northern Europe; they are distinguished as 

 follows : — 



Thorax distinctly margined at the sides, quadrate ; mandibles not promi- 

 nent. Sphalma. 

 Thorax not margined, more or less oval ; mandibles exserted ; 



Lateral sutures of thorax distinct ; third joint of antennae not longer 

 than the fourth ; 

 Head not narrowed behind the eyes ; tibial spurs well developed. 



Crymodes. 

 Head distinctly narrowed behind the eyes; tibial spurs small. 



Boros. 

 Lateral sutures not visible ; third joint of antennae longer ; 



Mandibles with one tooth ; body depressed; elytra striate. Pytho. 



Mandibles serrate; body subcylindrical ; elytra confusedly piiiu- 



tured. Priognathus. 



