650 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.39. 



Habitat. — Dallas, Texas, May 22, 1906, at flowers of Engelmannia 

 pinnatijida Torrey and Gray (W. S. Pierce) ; also one from Dallas, 

 May 17, 1908 (F. C. Bishopp). Perhaps a distinct species, but cer- 

 tainly very close to N. wheeleri, which is known from a single speci- 

 men. These species fall in a little group, in which the coxal spines 

 are not distinctly developed, and yet the insects accord in general 

 with the subgenus Micronomada. 



Type.—Csit. No. 13432, U.S.N.M. 



The following key contrasts the members of this group : 



Mesothorax at least largely red (Texas) 1. 



Mesothorax black without red 2. 



1. Markings yellow; pleura with a yellow spot wheeleri Cockerell. 



Markings cream-color; pleura without a yellow spot engelmannix Cockerell. 



2. Markings yellow (Virginia) mimula Cockerell. 



Markings creamy-white (Washington State) jennei Cockerell. 



Since the above was written I have examined two males of N. 

 wheeleri engelmannix collected by Mr. C. L. Marlatt in Riley County, 

 Kansas, September. They have the following distinctive characters : 



Length about 9^ mm.; coxal spines absent; face light lemon yellow 

 up to level of antennse, the lateral face marks extending obliquely 

 upward laterally, ending in a sharp point on orbital margin near 

 level of middle of scape; supraclypeal mark square; lab rum, and 

 base of mandibles broadly, pale yellow; posterior orbital margin 

 narrowly pale yellow ; scape greatly swollen, entirely hrigJit ferrugi- 

 nous red; flagellum darker red; third antennal joint much longer 

 than fourth; mesothorax very densely punctured, entirely black; 

 metathorax black, with a small red spot on each side; upper bor- 

 der of prothorax, tubercles, tegulse, scutellum, and postscutellum 

 cream-color; pleura with a very large red patch, inclosmg a variable 

 yellow one; legs red, hind coxae with a large whitish spot; abdomen 

 like that of female; apical plate broad and rounded, with a feebly 

 indicated notch. Some one had labeled this ^'heilighrodtii Cresson ? ". 

 It is entirely different from the described male of heilighrodtii, which 

 (according to Viereck, who examined the type for me) has a slender 

 scape. I have long thought that the described male of heilighrodtii 

 did not truly belong with the female, but the female of the present 

 insect is known, and is quite distinct from heilighrodtii. 



NOMADA RUBICUNDA Olivier. 



Liberty, Texas, 2 females, March 18, 1908 (E. S. Tucker). 



NOMADA ARTICULATA Smith. 



Mound, Louisiana, April 2 (F. C. Bishopp) and May 12 (C. R. 

 Jones). Boulder, Colorado, nesting in my garden, June (Cockerell). 

 I examined the spine on the anterior coxa of a Louisiana male, and 

 found it about 150 /x long, very broad at base, hidden among plumose 

 hairs twice its length, which carry pollen. 



