Studies of North American Bees 8i 



margins, narrow lines extending downward in lateral supraclypeal and 

 upper clypeal sutures, apical half of mandibles, a broad median line and 

 feeble lateral lines on mesoscutum with its anterior and posterior margins 

 along sutures, propleura, depressed areas under wings and at sides of 

 mesoscutellum and metanotum, broad line in mesoscutellar-metanotal 

 suture, metapleura, and whole of propodeum black. Sides of propodeum 

 above with prominent projecting angles as in superba. Antennae wholly 

 bright red, joint 3 very distinctly exceeding 4. Head and thorax coarsely, 

 closely and shallowly punctured. Legs wholly red except the coxae behind, 

 which are black. Tegulae red. Wings subhyaline, broadly and deeply 

 darkened along apical margin, nervures and stigma pale reddish, basal 

 nervure distinctly but not greatly basad of transverso-medial nervure. 

 Tergum black with broad complete even yellow bands on tergites 1-6, 

 that on I median, those on 2-6 basal and involving most of the tergites. 

 Venter red, the base of sternite i and apical marginals of sternites 1-3 

 black or blackish. Pygidial area on tergite 6 broad, rounded, densely 

 covered with appressed hair. 



Type. — West Point, Cuming county, Nebraska, $. 



The absolute lack of any yellow ornamentation on the head 

 and thorax distinguishes this form from almost all of our species 

 of Holonomada, in fact it is in this respect aberrant from one 

 of the chief diagnostic characters of the subgenus, yet it is not 

 a Nomada sens, str., but a species closely related to N . superba 

 Cresson, if not merely an extreme color variation of that species. 

 Robertson mentions a variety of superba occurring in Illinois in 

 which the ornaments are all red except the yellow bands on the 

 tergites, and in which the mesoscutum may have two or four 

 rufous bands. Our form certainly resembles this but is even 

 redder, having the mesoscutum red except for a median and 

 very vague lateral lines, the mesopleura red and all of the legs 

 beyond the coxae red. N. {Heminoniada) coUinsiana Ckll. is 

 another species without yellow on the head or thorax, but in that 

 species joint 3 of antennae is a little shorter than 4, the band on 

 the first abdominal tergite is reduced to yellow lateral spots, the 

 hind femora have a broad black stripe behind, etc. A^. (Hemi- 

 nomada) placitensis Ckll. is also mostly red on the head and 

 thorax but is also quite distinct; compared with the type of 

 placitensis in the U. S. National Museum nebrascensis differs 

 from placitensis in having the third antennal joint distinctly 



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