BEMBIDIIN.E 155 



V 



Group XVI assimile 

 Subgenus Diplocampa Bedel 



This group is as well defined and sharply delimited as Lopha, the 

 peculiarity here being the very convergent and anteriorly connivent 

 frontal sulci. These sulci do not actually coalesce at the epistomal 

 apex, but expand theretoward, so that at the extreme apex they are 

 usually in mutual contact, separated by a gradually acute convex 

 intermediate surface. Outside each sulcus at apex there is a feeble 

 oblong fovea, of the same nature as that previously noted under the 

 guadrimaculatum group, but there is no further analogy between 

 Diplocampa and Lopha, except in the row of punctures before the 

 thoracic base and in the general characters of the genus Bembidion. 

 In the more typical species there is an external posterior reddish 

 spot on each elytron, as in sulcatum, but a considerable number of 

 species have no trace of the spot, the elytra being uniform in color- 

 ation. Our species are rather numerous, those represented in my 

 collection being determinable as follows: 



Elytra alutaceous and micro-reticulate throughout; .body somewhat 

 stouter than usual 2 



Elytra polished, not micro-reticulate 3 



2 Body oblong-suboval, moderately convex, alutaceous, the type black- 

 ish, the elytra each with a large external spot at apical fourth and 

 the apex pale, the two connected broadly along the margin; under 

 surface red-brown, the legs pale; head four-fifths as wide as the pro- 

 thorax, the sulci deep; antennae slender, pallid, the medial joints 

 between two and three times as long as wide; prothorax two-fifths 

 wider than long; base narrower than the truncate apex and nearly 

 three-fourths the maximum width; sides strongly rounded to the 

 basal parallel part, which is a fifth or sixth the total length; basal 

 impression punctate but interrupted medially; foveae smooth, deep, 

 rounded, next to the short and rather indistinct carina; margins 

 rather widely and strongly reflexed; elytra barely one- half longer 

 than wide, nearly two-thirds wider than the prothorax, slightly 

 wider behind the middle than at base, the sides somewhat arcuate; 

 humeri rather rapidly rounded; striae moderate, scarcely impressed, 

 obliterated in apical fourth, the seventh a row of fine punctures, 

 not extending to the middle; punctures fine and unusually close- 

 set, traceable to the declivity; foveae before basal and before apical 

 third. Length ( 9 ) 3-4 mm. ; width 1.3 mm. California (St. Helena, 

 Napa Co.) digressum n. sp. 



Body stout, convex and ventricose, feebly alutaceous, black, the posterior 

 maculation as in the preceding; under surface black, the legs piceo- 

 rufous; head slightly though evidently narrower than the prothorax, 



