NATURAL SCIENCES OF PHILADELPHIA. 303 



PTEEOSTICHUS. 



Division 1. Dorsal punctures wanting ; marginal stria single. 



A. Posterior tarsi stout, not grooved on the outer side ; epistoma and 

 labrum emarginate ; prosternum feebly margined behind. 



Hammatomerus Chaud. 

 Joints of hind and middle tarsi % J inflated at tip. 



1. morionides Chaud. 

 Joints of hind and middle tarsi % 9 normal. 2. tarsalis n. sp. 



B. Posterior tarsi slender, first joint with two grooves and an inter- 



vening ridge on the outer side ; prosternum (except in P. 2)lanctu9) 

 strongly margined behind ; base of prothorax margined towards the 

 sides. 



A. Sides of prothorax crenato-dentate : 



Prothorax feebly narrowed behind, basal foveas large, bistriate, elytra 

 opaque, deeply striate. 3. crenicolUs u. sp. 



B. Sides of prothorax entire, not serrate : 



a. Prosternum scarcely margined behind : 



Outer basal stria of prothorax distinct, humeri not dentiform. 



4. flanctus Lee. 



b. Prosternum distinctly margined behind : 



a. Prothorax feebly narrowed behind, and slightly sinuate on the sides, 



hind angles rectangular; 



* Humeral angles dentiform : 



Hind angles of prothorax distinctly carinate, outer basal stria long. 



5. hereulaneus Mann. 

 ** Humeral angles not dentiform ; sides of elytra more rounded near the 



base : 

 Base of prothorax not depressed near the angles, outer stria a feebly 



impressed fovea ; algidus Lee. 6. v(cUd2is'Dei. 



Base of prothorax flattened, more narrowed, outer stria short, feeble, 



general form more elongate ; inornatus Bland. 7. protractus Lee. 

 Base of Jn-othorax less flattened; outer stria vague or wanting, sides of 

 prothorax oblique, scarcely sinuate behind ; sides of elytra more 

 parallel than in validus ; 

 Scutellar stria distinct (as in the other species of the group); calif or- 



nicus X Lee. 8. vicinus Mann. 



Scutellar stria very short ; form narrower. 9. longulus n. sp. 



b. Prothorax scarcely narrowed behind, outer basal impression verj' 



short, humeri not dentiform, body small, narrow, sides of elytra 

 parallel; linearis Lee. 10. angustus De]. 



c. Prothorax a little more narrowed behind, flattened at the base, sides 



scarcely subsinuate, hind angles rectangular, feebly explauatc, inner 

 basal stria long, outer one nearly obsolete ; humeri dentiform : 



* Scutellar stria short : 



Elytra with a purple reflection. * 11. ametliystiniis Dej. 



