THE CANADIAN ENTOMOLOGIST. 305 



DESCRIPTIONS OF SOME SPECIES OF COLEOPTERA 

 OCCURRING NEAR ALLEGHENY, HERETOFORE 



UNDESCRIBED. 



BY JOHN HAMILTON, M. D., ALLEGHENY, PA. 



Preparatory to the publication of a list of the Coleoptera of this vicin- 

 ity, it has been thought proper to characterize and name the following 

 forms : — 



Bembidium postfasciatum. — Coppery-bronzed, dark beneath, elytra 

 pallid, two dark fasciae. Head convex, impunctate, longitudinally 

 impressed on each side between the eyes, coppery-bronzed ; antennae 

 with three basal joints pale, the others fuscous ; thorax quadrate, base 

 and length equal, wider at middle, base truncate, basal striae double, hind 

 angles rectangular, carinate, dorsal line deep, coppery-bronzed, often 

 tinted green in the basal impressions ; elytra pallid, silvery white in life, 

 elongate oval, broadly deeply impressed transversely behind scutellum, 

 deeply striate, striae dilated before middle and coarsely punctured, punc- 

 tures finer towards apex, intervals convex, third bipunctate, a broad un- 

 dulated dark fascia behind middle, another before apex sometimes inter- 

 rupted at the suture and sides j underside dark, often with a greenish 

 reflection; legs entirely pallid. Length, .18-. 21 inch. Characterized 

 from 8 examples. Habitat : Palludial places along streams ; not common, 

 but abundant when found. This species has been distributed as a variety 

 of dorsa/e, Say, from which it is abundantly distinct ; in that species the 

 head and thorax are brilliant green, the impressions of the thorax less 

 dilated, the striae of the elytra finer, not dilated near base and with finer 

 punctures, the intervals flat ; the fasciae narrower and less conspicuous, a 

 greenish space around the scutellum and scarcely evidence of a trans- 

 verse impression. 



Platynus parmarginatus. — Elongate, depressed, dark above, antennae, 

 mouth parts, underside, epipleurte and reflexed margins of thorax ferru- 

 gineous, with a tendency to piceous on the abdomen. Head with deep 

 frontal impressions, a little narrower than the thorax within the marginal 

 reflexions ; thorax quadrate, widest at middle, narrowed to apex and 

 base by a curved line, anterior angles prominent, obtusely rounded, 

 posterior obtuse, side-margins uniformly and widely reflexed, discal line 

 fine not reaching base, length and greatest width equal ; elytra deeply 

 sinuate at apex, striate, intervals convex, the third with four punctures. 

 Length, .30-.38 inch. Characterized from 30 examples. Habitat : 



