1875.] 147 |P sten Sacken. 



The yellow spots on the second segment (in all my 3 americanus) do 

 not touch the lateral margin ; the black interval, although small, is 

 distinct; in all my <S abbreviatus these spots distinctly come in con- 

 tact with the lateral margin. The oral margin is not infuscated 

 here (except, of course, at the point of contact with the facial brown 

 stripe). Attention should also be paid, in both sexes, to the differ- 

 ence in the extent of the black coloring of the cheeks, as described 

 above. 



I hardly doubt that this is the S. americanus of Wiedemann. A 

 doubt might arise on account of the allusion to this species which 

 Wiedemann makes in his short description of S. concavus (1. c, p. 

 130, 24), from which it would appear that the crossbands of the 

 present species are notched. I suspect that Wiedemann had Say's 

 comparison of S. concavus and ribesii in mind, and inadvertently 

 applied it to S. americanus. 



6. S. contumax n. sp. 



Male and female. Eyes distinctly pubescent ; face with a bluish 

 reflection, sometimes almost concealing the dull brownish yellow 

 ground color; cheeks and oral border broadly black; front very 

 broad in the female, black, clothed with grayish pollen ; in the male 

 with a bluish reflection ; vertex greenish black, metallic. Antennae 

 black, inserted on brownish yellow ground; thorax greenish bronze 

 color, with indistinct longitudinal stripes of an opaque brownish ; 

 dorsum beset with brownish, pleurae with brownish fulvous erect pile; 

 scutellum dull yellowish, with a bluish reflection. Abdomen black, 

 very hairy, with three pairs of oblong, transverse, straight, brownish 

 yellow spots, which, as a rule, do not reach the margin, but some- 

 times emit an indistinct prolongation anteriorly, which touches it; 

 the last two segments are bordered with yellow; the pile on the abdo- 

 men, yellow and black, is, especially in the male, long, erect, and 

 rather conspicuous. Femora (of the male) black on their proximal 

 half, often beyond, hind femora up to four-fifths of their length ; 

 tibice brownish yellow ; tarsi black. In the -female the femora are 

 black at their bases only. Wings hyaline, sometimes tinged with 

 brownish; stigma brownish; third longitudinal vein nearly straight. 



Length about 9.5 mm. 



Hah. White Mountains, N. H.; I brought home three males; Mr. 

 G. Dim mock gave me two females, labelled Mt. Washington, Alpine 

 region. 



The facial tubercle in this species is very salient, the whole lower 



