Picrostichma.'] adephaga. HO 



Pterosfichus, and Plafydenis ; Scliaum includes the Anchomenina, 

 Amarina, and also Patrobus, Pogonuti, &c., thus forming so unwieldy a 

 tribe that it is totally incapable of any reasonable dehnition. The tiil)e, 

 as here laid down, is separated from the Zabrina by the fact that the 

 head has two supra-orbital setigcrous punctures instead of one, from the 

 Amarina l\y having the terminal joint of the labial palpi as long as or 

 longer than the preceding, which is bisetose in front, instead of being 

 shorter and plurisetose, and from the Anchomcnina by having the 

 epipleuraj interrupted at the level of the last abdominal segment, instead 

 of being continuous to apex. 



I. Mandibles long and prominent, more than half the length 



of the head ; maxillae not hooked at the tip SXOMIS, Clairv. 



II. Miindiblcs not prominent, shorter than half the length of 



the head ; maxillaj hooked at the tip. 

 i. Tooth of nieiituin simple; thorax with anterior margin 



produced in front, hisiuuate . Plattdkrus, i'/e^A. 



ii. Tooth of mentum emarginate ; thorax with anterior 



margin not produced in front, straight or almost 



straight Pteeosticiius, Er. 



STOiraiS, Clairville. 



This genus contains only four species, three of which are European : 

 they are chiefly remarkable for the size of their mandibles. 



S. pumicatus, Panz. Elongate, pitchy black, shining ; head narrow, 

 palpi and antenna? red ; thorax elongate, strongly rounded behind anterior 

 angles, very much contracted behind, posterior angles acnte and ])ro- 

 niinent, disc convex, central furrow well marked, base with an oblong 

 fovea on each side ; elytra rather long, ovate, with nine strongly punc- 

 tured, almost crenulate striae ; legs red. L. 6-8 mm. 



Under stones, flood refuse, &c. ; not uncommou in England and Ireland, although 

 never taken in any one place in abundance. Scotland, not comuiou. Lowlands. 



PZiATYDERUS, Stephens. 



The species of this genus approach closely to the Calathi ; they arc 

 about twenty-four in number (about twelve, according to M. Bedel, who 

 considers the number much exaggerated), and inhabit the Europeo- 

 !Mediterranean region and the Canary Islands, Sec. We possess one 

 species only as British. ^I. Bedel places the genus between Sphndnia 

 and Calathus, and considers that it has nothing to do with Pterosliclius 

 at all. 



P. ruficollls, ^[arsh. Elongate, flat, pitchy-black or ferruginous ; 

 head pitchy very shining, antenna? and palpi lighter or darker rod ; thora.x. 

 always more or less rufesoent, about as long as broad, anterior angles 

 siunewhat prominent, sides cin-vcd gradually to Itaso, posterior angles 

 obtuse almost rounded, with a strongly impressed dorsal furrow, and a 



