302 PROCEEDINGS OF THE ACADEMY OF 



THE PTEROSTICHI OF THE UNITED STATES. 

 BY JOHN L. LECONTE, M.D. 



Since the i)ublication of my synopsis of the species of Pteros- 

 tichus and allied genera inhabiting temperate North America,' 

 the additions to our fauna haA'e been quite appreciable, but what 

 is of greater importance, by the kindness of friends in Europe, 

 authentic specimens have been procured of most of the species 

 which at that time were unknown to me. It has, therefore, ap- 

 peared to me useful to place in a condensed form the results of a 

 more recent study of the species in my collection, in order to 

 facilitate the recognition of the numerous forms in this somewhat 

 difficult genus. 



I have, with greater material and more careful study, been 

 obliged to modify the generic table given in the work just cited, 

 to such an extent as to place Pcecilus as a minor group of Fteros- 

 tichus, and to elevate Fiesmus, on account of its absolutely simple 

 mentum tooth, to the rank of a genus. 



I would, therefore, propose this new scheme of arrangement. 



Mandibles striate ; elytra with one dorsal puncture. Evarthrcs. 



Mandibles not striate : 

 Mentum tooth emarginate : 

 Ligula cariuate : 

 Metatlioracic episterna long. Lofhoglossus. 



Metathoracic episterna short. Holciophokus. 



Ligula not carinate : 



Front tarsi of % normally dilated. Pterostichus. 



Front tarsi of % obliquely dilated. Loxakdrus. 



Mentum tooth entire, rounded at tip. Pies.mus. 



It is worth}' of remark, that while in Europe many species occur 

 in which the last ventral segment of the % is crested or impressed, 

 four have thus far been found in America. On the Pacific slope 

 JSolciophorus ater is the only example, and in the higher parts of 

 the Alleghanies P. mancus, diligendus, and lubricus. 



' Journal Acad. Nat. Sci., Philada., 2d, ii. 22.j. (1852.) 



