234 LECONTE— SYNOPSIS OF PTEROSTICHUS. 



E. colossus. By an error which is entirely unaccountable, I have in the Annals of 

 the Lyceum placed Feronia heros Say, as synonymous with F. americana'De/. The 

 latter will be found in the first division of the present genus. 



28. E. furtiv.us, thorace subquadrato, postice angustato, lateribus late rotundatis, postice brevius 

 sinuatis, basi rugoso, linea transversa anteriore tenui, elytris striato-punctulatis, interstitiis planis. 

 Long. -6. 



One male, Lake superior. This species is different in form from the others of this 

 division, and approaches more closely to E. orbatus of division (b). 



Shining black. Thorax wider than the head subquadrate, somewhat cordate, 

 broadly and obliquely rounded on the sides, moderately narrowed behind, sides 

 slightly sinuate at the posterior angles, which are rectangular, and but little promi- 

 nent ; anterior transverse line fine, near the margin, dorsal line almost entire ; basal 

 impressions deep, rugous, strise distinct, the inner one a little longer, carina distinct. 

 Elytra a little wider than the thorax, somewhat rounded on the sides, strise deep, 

 finely punctured, interstitial spaces almost flat; outer marginal stria equidistant from 

 the eighth stria and the margin. Antennae rufo-piceous, black at base. 



29. E. mane us, thorace trapezoideo, postice angustato, lateribus late rotundatis, angulis posticis obtusis 

 subrotundatis, impressione basali elongata, lineari, punctoque ad angulum oblongo notato, eljtris non 

 latioribus convexis, profunde striatis. Long. -45. 



Nakutshi Valley, Habersham County, Georgia. This species differs from all the 

 preceding ones in having the first joint of the abdomen scarcely impressed. The 

 scutellar stria of the elytra is punctiform ; the strise are a little less deep towards the 

 tip. The thorax has no transverse impressions, the basal impression is deep. The 

 last ventral segment in the male has a small transverse tubercle near the apex. 



PTEROSTICHUS Bon. 



Antennae basi non carinatae; mentum dente medio concavo, vel emarginato, vel obtuso; ligula subplana, 

 apice rotundato-truncata, paraglossis linearibus ea paulo longioribus; parapleurse vel elongatae vel breves- 

 elytra stria scutellari notata, punctis dorsalibus vel nullis, vel pluribus ; tibiae posteriores extus vix spinulosaa; 

 tarsi antici maris articulis tribus primis obcordatis, plus minusve emarginatis. 



A very numerous genus, and somewhat variable in generic characters, but which 

 may be easily divided in natural groups, by taking into account those structures upon 

 which specific characters are impressed. The variations in generic characters can 

 scarcely be used for systematic division, since every imperceptible gradation occurs 

 between those with short and those with long epipleurse ; those with the tarsal 

 grooves on the outer margin deep, and those with the same grooves nearly obsolete; 

 and also between those with a bifid tooth in the chin, and others in which Ihe tooth 

 is simply obtuse. The marginal stria (the 9th) is never approximated to the ocellate 

 punctures. The variations in the characters above referred to will be pointed out 



