46 Trans. Acad. Set. of St. Louis. 



Andrena illinoensis Rob. form bicolor, n. f. 



Two female specimens agree with the normal form in all 

 respects except that the abdomen is reddish, except two black 

 spots on second segment indicating the position of the usual 

 foveae. 



A\DRENA MARIAE Rob. form CONCOLOR, n. f. 



This species was based on examples with the abdomen red. 

 I separate as a form the specimens which are entirely black. 

 The abdomen is usually all red or entirely black, only rarely 

 black with a trace of red. All of the males I have seen have 

 the abdomen black, or sometimes with more or less red. 



Andrena forbesii Rob. 



Andrena forbesii Robertson, Trans. Am. Ent. Soc. 18: 59. 9- 1891. 



<j. — Closely resembles the male of A. rugosa Rob., but has 

 the abdomen more closely and strongly punctured, the margins 

 less widely depressed, and the antennae more smooth and 

 shining. Length 8-9 mm. 



»' 



Andrena quintilis, n. sp. 



<j>. — Resembles A. forbesii; the head, except the elypeus, 

 more coarsely and less closely punctured, the pubescence 

 thinner, shorter and paler ; thorax above more coarsely and 

 sparsely punctured, pubescence densely plumous, but short and 

 thin, except about shoulders ; metathorax coarsely reticulated, 

 the inclosure less distinct ; abdomen more strongly and much 

 more densely punctured, except the base of first segment, 

 which is more shining and less closely punctured ; fasciae 

 more dense and whiter, interrupted on second segment. 

 Length 10-11 mm. 



Carlinville, Illinois, 4 o_ specimens, taken July 19th, 26th 

 and 29th, on flowers of Pycnanthemum linifolium Ph. Of 

 forty-two species occurring in my neighborhood, this is the 

 only one flying at that time. 



Of the species of Andrena known to me this has the 

 abdomen most densely punctured. The scutellum and post- 

 scutellum resemble those of A. nuda; the pubescence also 

 like that of A. nuda, but more abundant on mesonotum. 



