IS THE CANADIAN ENTOMOLOGIST. 



SOME NEW OR LITTLE-KNOWN BEES— II. 



BY CHARLES ROBERTSON, CARLINVILLE, ILLINOIS. 



In my neighbourhood I find the typical Andrena Cressonii, Rob., and 

 the form described below as A. dubia, the latter more rare. To compare 

 this with the form described as A. Bridwellii, Ckll., I have obtained from 

 Mr. Bridwell for examination thirty-three specimens taken by him at 

 Baldwin, Kansas, and labelled A. Cressonii, A. Kansensis, and A. 

 Bridwellii. 



A. Kansensis is the same as A. Cressonii, the colour of the pubescence 

 being characteristic of unfaded specimens. Local specimens sometimes 

 have the hind tibia; and tarsi ferruginous in both sexes. 



A. Bridwellii seems to be the common form at Baldwin. It differs 

 from the typical A. Cressonii in the characters mentioned below. Some 

 specimens have the flagelium testaceous beneath and some have the tarsi 

 and hind tibia? more or less ferruginous. It is intermediate between 

 A. Cressonii and A. dubia. If I should find A. Bridwellii in my 

 neighbourhood, I would regard them all as A. Cressonii. As it is, they may 

 be only variant forms of A. Cressonii, but I have thought it well to 

 separate A. dubia provisionally and to let A. Bridwellii stand on the 

 same basis. The validity of both depends on the discovery of characters 

 which will enable one to separate the females from each other and from 

 females of A. Cressonii. 



Joint 3 of antennae shorter than 13, about as long as 5, entire apical 

 margin of clypeus black, lateral face marks small or 



wanting A. dubia, sp. nov. 



Joint 3 of antennae as long as 13, and as long as 4 and 5 together. 

 1. — Middle of anterior margin of clypeus black, lateral face marks 

 large A. Cressonii. 



Entire apical margin of clypeus black, lateral face marks small or 

 wanting A. Bridwellii. 



•a 



Dialictus, gen. nov. 

 This is proposed as a new genus for the reception of Halictus 

 afiomalus, Rob., as the type. The species was described from two 

 specimens, and I suspected that I might find examples with three 

 cubital cells and that the males might not differ from the ordinary 

 dull greenish Halictus, except in the venation. But the male differs from 

 all of those species of Halictus known to me in having the antennse 

 short, the joints hardly longer than wide, joint 3 hardly longer than 



