BEMBIDIINJE 47 



mentum varies from very broadly obtuse, in the nigrum concolor 

 section, to obtusely triangular, as in the large majority of other 

 sections of the group. The coloration of the elytra is often uni- 

 form black or brown, but may have nubilous paler basal and sub- 

 apical areas, or may assume such special forms as seen in scopu- 

 linum, where the posterior elytral spots are almost as in certain 

 species of the as simile group, or in albidipenne, where the elytra 

 are pale, with dark apex and dark post-median fascia of irregular 

 form. Again the elytra may be black, with a posterior pallid fascia 

 as in liaplogonum Chd. (mannerheimi Lee.). 



The species known to me may be assigned to eleven distinctly 

 circumscribed sections as follows, all having two dorsal fovese on 

 the elytra, excepting rickseckeri: 



Prothorax as wide at base as at apex and sometimes wider 2 



Prothorax always distinctly narrower at base than at apex 4 



2 Eighth stria rather distant from the margin, it, as well as the reflexed 

 margin, coarsely and conspicuously punctate; body small, convex, 

 the striae obliterated behind; legs rufous (nigrum} i 



Eighth stria near the margin as usual, it, as well as the reflexed margin, 

 distinctly though not coarsely punctate; body more oblong and less 

 convex, with broader prothorax, the striae more or less abbreviated; 

 legs blackish (quadrulum) 2 



Eighth stria impunctate, deep and near the margin as usual 3 



3 Body small, black and polished as a rule, the head small, the pro- 

 thorax nearly quadrate (concolor} 6 



Body larger, diversified in color, polished, the head well developed; 

 striae entire or abbreviated, the seventh strong and entire to obso- 

 lete (transversale) 17 



4 Eighth stria distant from the margin, consisting of an unimpressed 

 series of very coarse punctures, the reflexed margin similarly punc- 

 tate; body small, convex and with abbreviated striae, resembling 

 nigntm superficially (brevistriatum} 29 



Eighth stria near the margin, deeply impressed and impunctate as 

 usual 5 



5 Body small, polished, black; striae more or less abbreviated, the head 

 moderately large (californicum} 30 



Body larger, convex, with relatively small head as a rule; striae more or 

 less abbreviated, the seventh wanting or very feeble. . (ustulatum) 37 



Body similarly larger but usually broader and less convex than in the 

 ustulatum section and with small or moderate head, but differing 

 in having entire striae, the seventh always distinct and entire or 

 nearly so, the foveae usually rather more conspicuous. 



(honestuni) 59 



Body small or moderate, generally somewhat depressed and with the 

 head nearly as in the two preceding, the striae entire or nearly so, 



