Studies of North American Bees g 



either is the presence of a hairy tubercle or rudimentary spine 

 on the front coxae and the sHghtly moniliform antennae, thus 

 showing relationship to the denticulata-elccta group. 



Nomada (Nomada) vicina stevensi Swenk. 



Additional metatypes examined from the type locality (Fargo, 

 North Dakota) are as follows : August lo, 1912, on Grindclia 

 squarrosa (3538, O. A. Stevens), i (^ ; August 21, 1912, on same 

 plant (3807, 3808, 3809), 3 (^; August 26, 1912, on Solidago 

 canadensis (3933), i ?; September 6, 1912, on Melilotus alba 

 (4132), I 5- At Medora, North Dakota, August 30, 1914, on 

 Solidago rigida, Mr. Stevens took two specimens (8466 and 

 8480), I $, I c^, and at Schafer, North Dakota, September 5, 

 1914, on the same plant another male (8507). This gives a 

 season for the bee of August 7 to September 6. The additional 

 three females bear out the characters of the subspecies but are a 

 little smaller than the type (7-8 mm.) and 4132 has the pale 

 spots on tergite i nearly obsolete and the other abdominal macula- 

 tions more yellowish than usual, almost as yellow as in typical 

 vicina. The same deepening of the yellow is shown in one of 

 the males (3807). However the color differences are very re- 

 liable in the males, and I svispect stevensi will ultimately have to 

 be considered a distinct species. 



Nomada (Heminomada) elrodi Cockerel!. 



A male is before me from Fedor, Texas, March 20, 1905, on 

 Prumis (Rev. G. Birkmann). It is not different in any way 

 from some of the series of Nebraska males. I have also to 

 record a series of six males collected April 26, 1913, on Leon- 

 todon (Taraxacum) taraxacum at Lincoln, Nebraska, by R. W. 

 Dawson. We have not previously collected the species on that 

 plant. 



Nomada (Heminomada) maculiventer n. sp. 



2- Length 7.5-9 mm. Bright dark red; ends of mandibles, elongate 

 oval spots above insertion of antennae connected medially, sutures around 

 supraclj'peus and upper clypeal sutures, oval spot involving ocelli, bar on 

 posterior margin of cheeks, two large spots on propleura, narrow anterior 

 and posterior borders and a depressed median line on mesoscutum, de- 



16^ 



