236 LECONTE— SYNOPSIS OF PTEROSTICHUS. 



in their form ; the dilated joints are broad and almost transverse in the first two 

 species, while in the others they are distinctly longer than wide; in both sexes of 

 P. rostratus and P. grandiceps, the fourth joint is scarcely narrower than those which 

 precede, and the last joint is much flattened and broader than in the other species. 

 The grooves on the outer margin of the posterior tarsi are not deep. This group 

 corresponds in part with Chaudoir's genus Haploccelus. 



1. P. rostratus, capite magno, mandibulis porrectis, thorace lateribus vix rotundatis, basi subbistriato, 



elytris thorace non latioribus, striis profimdis, obsolete punctulatis. Long. -65. 

 Feronia rostrata Newman, Ent. Mag. 5, 387. . 



Southern and Western States ; the striae of the elytra are sometimes entirely 

 smooth, sometimes slightly punctulate. .The male has a shallow round impression on 

 the last ventral segment. 



2. P. grandiceps, capite magno, mandibulis porrectis, tborace lateribus vix rotundatis, basi vix 



bistriato, elytris thorace non latioribus, striis profundis punctatis. Long. -54. 

 Stereocerus grandiceps Lee. An. Lye. 4, 336. 



One female, New York. Very similar to the preceding, but besides the stronger 

 punctuation of the strke of the elytra, the outer impression at the base of the thorax 

 is less distinct, and there is no carina near the margin ; the lateral margin is also 

 finer ; the scutellar stria of the elytra is indistinct. 



3. P. ad ox us, thorace capite latiore, tenuiter marginato, postice angustato, lateribus modice rotundatis, 



angulis posticis denticulatis, basi recte truncato, unistriato, elytris vix latioribus striis valde profundis, 



interstitiis convexis. Long. -53. 

 LeConte, Agassiz Lake Superior, 207. 

 Feronia adoxa Say, Trans. Am. Phil. Soc. 2, 46. 

 Feronia (Platysma) tristis Dej. Sp. Gen. 3, 324. 

 Feronia interfector Newman, Ent. Mag. 5, 387. 



Common in every part of the Atlantic Zoological district. The last ventra^ 

 segment of the male has two deep impressions, separated by a longitudinal elevation. 



4. P. sustentus, thorace capite latiore, distinctius marginato, postice angustato, lateribus modice 



rotundatis, angulis posticis subrectis, basi recto, unistriato, elytris vix latioribus, striis valde profundis, 

 interstitiis convexis. Long. -52. 



One pair, Nakutshi Valley, Habersham County, Georgia. This species is 

 extremely similar to P. adoxus, but the thorax is more broadly margined, and the 

 posterior angles are not denticulate ; otherwise there is but little difference. In my 

 two specimens the feet are rufo-piceous. The joints of the tarsi of the male are a 

 little narrower and less emarginate than in P. adoxus ; the last ventral segment is 

 carinate and less deeply impressed. 



5. P. reieetus, thorace capite latiore, tenuiter marginato, postice angustato, lateribus modice rotundatis, 



angulis posticis apice rotundatis, basi recto utrinque striato, elytris vix latioribus, striis valde profundis, 

 interstitiis convexis. Long. -53. 



