THE ENTOMOLOGIST 



Vol. XL.] MAY, 1907. [No. 528. 



NEW AMERICAN BEES.— IV. 

 By T. D. A. Cockerell. 



Bombus rufocinctus astragali, n. var. 



? . Similar to B. rufocinctus iridis (Ckll. & Porter), but the broad 

 black band of the abdomen is without any red. This looks exactly 

 like B. edwardsii, Cresson, and has until now always passed as that 

 species. On comparing it with Pacific coast edwardsii, I noticed a 

 difference in the length of the malar space, and wrote to Mr. Viereck 

 to examine the material labelled edwardsii in the Cresson collection. 

 This he kindly did, reporting as follows : — 



(1.) Malar space about half as long as wide. Two females, Colo- 

 rado ; one female, Washington State ; one female, Montana. 



(2.) Malar space a little more than half as long as wide, rather 

 quadrate. Female, California ; female, Nevada. 



The latter is the real edwardsii. I had labelled the Colorado insect 

 as anew variety of edwardsii ; but Mr. H. J. Franklin, to whom I sent 

 a specimen, is confident that it is an extreme variety of B. rufocinctus, 

 the structural similarity outweighing the remarkable colorational dif- 

 ferences. 



Hah. Boulder, Colorado, June 9th, 1905, at flowers (white) 

 of Astragalus sp. (W. P. Cockerell). Also Ward, Colorado, at 

 Phacelia (Cockerell), and Florissant, Colorado (Rohwer). 



Nomada ceanothi, sp. nov. 

 2 . Length about 7 mm. ; belongs to Nomada as restricted by 

 Robertson, and is very close to N. florilega, Lovell & Ckll. (from Maine), 

 from which it differs as follows : — Red of clypeus extending upwards 

 in middle line, almost to antennae ; third antennal joint conspicuously 

 shorter, its length little exceeding its apical breadth ; flagellum more 

 slender ; hind femora less infuscated ; second abdominal segment with 

 a pair of extremely large lemon-yellow spots, more or less pyriform in 

 shape ; third with large yellow spots ; fourth without spots ; fifth with 

 a pair of very dull spots. Characters distinguishing it from other 

 allied species (such as N. illinoensis and N. sayi) are as follows : no 

 trace of yellow at lower corners of face ; antennae long, fourth joint a little 



ENTOM. — MAY, 1907. K 



