Robertson — Some Illinois Bees. 49 



convex, finely roughened, with rather large and sparse punc- 

 tures; process of labrum long, narrow; front below ocelli 

 finely striate ; facial grooves narrow, extending below anten- 

 nae, appearing fulvous; antennae black, short, joint three 

 longer than four and five together, these subequal ; meso- 

 notum and scutellum finely roughened, rather sparsely punc- 

 tured, not shining; metathorax rugose reticulated, inclosure 

 small, quite rough ; wings subhyaline, nervures honey-yellow, 

 stigma darker, second subraarginal cell about half as long: as 

 third, receiving recurrent nervure just beyond middle; ab- 

 domen smooth, shining, almost impunctate, especially the 

 first segment, with thin pale pubescence, segments 2-4 with 

 narrov pale-testaceous margins and thin whitish fasciae, anal 

 fimbria blackish. Length 10 mm. 



Carlinville, Illinois; 2 5 specimens. This species also 

 resembles A. mandibular/ s. 



Andrena nasonii Rob. 



Andrena nasonii Robertson, Trans. Am. Ent. Soc. 22 : 120. 9- 1895. 



g. — Closely resembles the female ; abdomen more shining, 

 pubescent fasciae almost obsolete; face narrowed below; 

 clypeus finely roughened, with rather coarse, shallow punc- 

 tures, bearded with long, thin, white pubescence; antennae 

 long, joint three about as long as four, shorter than five. 

 Length 6-8 mm. 



Carlinville, Illinois; 15 5, 4 ^ specimens. 



Andrena robertsonii D. T. 



Andrena serotina Robertson, Trans. Am. Ent. Soc. 20 : 148. $ (not^). 

 1893. 



$. — Closely resembles the female ; abdomen less fasciate 

 with pubescent bands; clypeus yellow; third joint of antennae 

 longer than fifth ; cheeks narrow, without obtuse angle ; sixth 

 ventral segment of abdomen with reflexed dentiform angles. 

 Length 7 mm. 



Carlinville, Illinois; 41 5, 7 ^ specimens. Resembles the 

 male of A. bipunctafa, but may be readily distinguished by 

 its cheeks being more narrow, without obtuse angle, more 

 rugose inclosure of metathorax and dentiform reflexed angles 

 of sixth ventral segment. 



