584 PROCEEDINGS OF THE ACADEMY OF [A-Ug., 



after Prof. ^I. J. Elrod, the Montana naturalist. Another (with meso- 

 thorax entirely black) is from Cedar Bluffs, Neb. (L. Bruner, No. 30). 

 Nomada sulphurata, Smith. 



This has been regarded as a synonym of A^. lulcola, l^ut it appears 

 to me to be a perfectly valid species. I thought at first that N . luteo- 

 loides, Rob., might be a synonym of it, but the males at least certainly 

 appear to be different. Compared with N. hiteoloides, the male of A'. 

 sulphurata has a larger thorax and broader abdomen ; the j^leiu'a shows 

 a large irregular yellow mark, and a yellow spot beneath the wings; the 

 scutellum is all yellow, the lateral margins of the mesothorax are yellow, 

 and the metathorax has yellow lateral marks. The scape is more 

 swollen, there is a yellow spot in front of anterior ocellus, and the \A'hole 

 of the face below the level of antennje is yellow. The hind margins 

 of the ventral surface of abdomen are broadly pale ferruginous. The 

 flagellum is denticulate or warted beneath on the fifth to seventh seg- 

 ments from the end. The female has the mesothorax black, usually 

 but not alwa^^s with reddish-yellow stripes. The material of A^. sul- 

 phurata before me, consisting of Id" , 5 9, was collected by Mr. Viereck 

 at Edge Hill, Pa., the male May 23, the females April 28 and May 5, 

 1901. 



Nomada rivalis, Cress. 



A male marked "W. T." (Washington State), from Acad. Nat. 

 Sci. Phila., is before me. A female, also marked ''W. T.," looks 

 as if it belonged with the male, but the basal nervure meets the 

 transverse medial, and the specimen is referred to A^. citrina. 



Nomada civilis, Cress. 



A male from the National iMuseum is labelled "Colo., 1871," and is 

 apparently from the Baker collection. I thought this might prove to 

 be the male of N . morrisoni, but a couple of females from Corvallis, 

 Ore., June 3, 1899, are so much like the male that I can onl}- refer them 

 to the same species. The characters given in the table separate them 

 from morrisoni. 



Nomada luteoloides, Rob., and N. luteola, Lap. 



A female from Georgia, sent to me by Mr. Fox as A^. luteola, has the 

 yellow of metathorax encroaching upon the enclosure, as Robertson 

 states for luteola, but the proportions of the antennal joints agree with 

 luteoloides. A male from Georgia, received with the female, has the 

 flagellum slightly denticulate beneath, and the orbits yellow except 

 at summit behind, so it ought to be luteoloides. Nevertheless, the den- 

 ticulation is feeble, and the anterior tibiie have a black mark behind; 



