NORTH AMERICAN HYMENOPTERA. 157 



pressed on apical poi-tion. Black ; maculated as in bigeminus, hut with whitish 

 and each tibia has a dark spot within, the femora are black except their apices, 

 and there are no spots on middle segment ; wings subhyaline throughout. Length 

 11-13 mm. 



% . — Differs from the %, of buieminiis only in its finer sculpture, particularly of 

 the abdomen, by the pale ornation, the presence of a dark spot on tibise within 

 and by dorsal abdominal segments 2-5 having a broad band. Length 7-12 mm. 



Colorado; South Dakota (Aldrich) ; Montana; Washington. 



29. Crabro bigeminus Patt. 



Crabro bigeminus Patton, Can. Ent., xi, p. 213. % 9 • 



9- — Head rather finely punctured, smaller than rafifemar, frontal impressed 

 line tolerably distinct; ocelli as usual, the space between the hind pair somewhat 

 less than that between them and the nearest eye-margin ; pronotum strongly 

 margined anteriorly, subdentate laterally ; dorsulum with rather close, strong 

 punctures, much less coarse than in rufifemur, and are most compact ante- 

 riorly ; scutellum punctured about like the posterior portion of dorsulum ; 

 mesopleurse tolerably coarsely striato-punctate, hut less so than in rufifemur; 

 mesopleurse with the medial furrow narrow, not deep, tolerably coarsely striato- 

 punctate, the striae usually distinct above, and particularly on posterior face, 

 where they are transverse, lateral ridges wanting, sides delicately striated ; 

 abdomen distinctly punctured, particularly the iirst dorsal segment, the second 

 ventral veiy sparsely punctured ; pygidium somewhat longer than in villosus and 

 rufifemur, slightly depressed on apical portion. Black: mandibles except apex, 

 scape, two large spots on pronotum, tubercles, episternum mesopleuralis more or 

 less, two small spots just anterior to the scutellum, which is rarely colored, meta- 

 notum, a large spot on the posterior face of middle segment laterally, extending 

 on the sides somewhat, femora above and beneath on apical portion, tibiie, tarsi, 

 except one or two apical joints, spots one at each side of abdominal segments 1-3, 

 those on segment 1 shortest, on segment 3 longest and narrowest and pointed 

 within, whereas those on the first two segments are obtuse, and a band on segments 

 4 and 5, yellow; femora, in part, rufous and black ; silvery pubescence on meso- 

 sternum rather prominent; wings subhyaline, slightly darker apically, nervures 

 and stigma testaceous. Length 12-14 mm. 



% . — Space between hind ocelli distinctly less than that between them and 

 nearest eye-margin ; punctures of head stronger and not as close as in the 9 J 

 pronotum strongly dentate laterally ; dorsulum with rather coarse, separated 

 punctures ; mesopleurse coarsely striato-punctiite ; sides of middle segment strongly 

 striated ; first joint of medial tarsi shorter than the following two united, not 

 produced at apex, the outer margin strongly angular, the second joint a little 

 produced at apex and slightly curved ; abdomen strongly punctured, particularly 

 the first and second dorsal segments, the remaining dorsal segments more finely 

 and closely punctured ; colored like the female, but the femora less black, and the 

 abdominal markings narrower. Length 12 mm. 



Massachusetts ; Connecticut (Patton) ; New Jersey ; Delaware ; 

 Georgia. Distinguished from rufifemur by the less coarse sculpture 

 and form of first medial tarsal joint ; from diledus it differs by the 

 darker markings, greater extent of yellow and rufous on the femora, 

 coarser sculpture of abdomen, etc. 



TRANS. AM. ENT. SOC. XXII. JUNE. 1895. 



