238 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 41. 



are yellow. Compared with N. semiscita this is larger and more 

 robust, with the ground-color of the first three abdominal segments 

 bright ferruginous, the postscutellum yellow or orange, and very 

 obscure light spots on the axillse and near the posterior corners of the 

 scutellum. The first r. n. joins the second s. m. in the middle, and 

 the eyes are olive-green. Venter of abdomen clear ferruginous, spar- 

 ingly marked with yellowish; lateral face-marks rather irregular, but 

 gradually narrowing above, to end in a line which nearly reaches the 

 top of the eye; hind femora blackened behind, but in front only at 

 base. 



Berkeley, Colorado, June 10, 1897 (collector unknown). I was 

 about to describe this as new, but on close comparison with N.frieseana 

 female, I am convinced that it is the hitherto unknown male of that 

 species. 



NOMADA TEXANA Cresson. 



Two females: Colorado (Baker 2095). The yellow markings are 

 paler than usual. 



NOMADA TARAXACELLA Cockerell. 



Four females: Colorado (Baker 2075). One is quite normal, except 

 that the face is broad; the other three lack the yellow markings at 

 the sides of the abdomen, and the lower corners of the face, though a 

 little pallid, are scarcely yellow. After careful comparison, I am 

 convinced that they are all one species. Eight males, also with 

 Baker's No. 2075, are, I think, certainly to be associated with them. 

 These males, however, can not be easily separated from N. modocorum 

 Cockerell. N. taraxacella was originally described as a subspecies of 

 N. ultima Cockerell. The types of N. ultima and modocorum both 

 came from Corvallis, Oregon, and I now believe they are the sexes of 

 one species. The Rocky Mountain taraxacella is readily separable in 

 the female, but the male is like that of modocorum, except that the 

 hair on inner side of hind basitarsus is pale fulvous, and the third 

 antennal joint is relatively shorter. The yellow bands along sides of 

 face may be swollen at the upper end. The scutellum varies as follows : 

 (1) All black, (2) with two minute red spots, (3) with two large red 

 spots, slightly confluent, (4) with two small yellow spots. 



Two female taraxacella are labeled "Colo. 2179," from the Baker 

 collection. 



NOMADA SAYI Robertson. 



Females: Colorado (Baker 1893); Westcliffe, Colorado, at flowers 

 of Erigeron radicatus, May 24, 1889 (T. D. A., Cockerell, 34). The 

 last was reported in the Wet Mountain Valley list as N. americana 

 var. valida. These are best distinguished from N. taraxacella by 

 the smooth shining abdomen, without the satiny, almost purplish 



