118 CIIAKLKS ROBERTSON. 



and sparsely punctured, disc of nietathorax with longitudinal rugte not reaching 

 apex ; abdomen shining, impunctate with very thin pubescence ; hind spurs with 

 few teeth. Length 6 mm. 



Hub. — Illinois ; five specimens. It closely resembles H. cephalicas, 

 but is distinguished by its face being broader above than below and 

 the flagellum being less slender, etc. 



Aiigochlora viridula Smith, Brit. Mus. Cat. Hym. i, 81, %, ; .1. Incidula 

 Smith, ibid. 81-82, 9— see Patton, Bull. U. S. Geo. Surv. v, ;«)6. 



.4ugoclilora fervi«la Smith. Brit. Mus. Cat. Hym. i, 81. 



For a l(jng tinn' I have known only the 9 <>f this, which I had 



determined as A. Jiumeralu Pttn, Patton's description seems to 



indicate no difference, except that the male does not have pale tarsi. 



Agapositenion viritlula F. ; Apis viriduJa F., Ent. Syst. ii, 342; Ayapoxte- 

 mon 7iigricornis Cress, (nee F.), Cat. Hym. N. A., 309; A. hicolor Rob., Trans. 

 Am. Ent. Soc. xx, 148. 



In Cresson's Catalogue the synonym of this species is not given 

 under Ar/apostevion, but under Apw ; .so I overlooked it and rede- 

 scribed the species as A. bieolor. 



Agaposlemon sericea Forst. ; Apissericea Forst., Nov. Spec. Ins. i, 91. 



As in the case, of the description of A. tricolor Lep., nothing can 

 be made out of the description of this insect, except that it is some 

 male Ayapodemon. 



Andrena viciiia Smith, Brit. Mus. Cat. Hym. i, 112, 9 ! ^- hirticeps Smith, 

 ibid. 116, % ; A. bieolor Rob. (uec F.), Trans. Am. Ent. Soc. xviii, 51. 



This is a common and very variable species. In Illinois the com- 

 mon form has the pubescence .of the head black, except a little 

 ochraceous about the base of the antennae and on the vertex ; some- 

 times there is no ochraceous pubescen(!e on head, except a slight 

 indication on the vertex. The thorax is ochraceous above, but sonje- 

 times this color extends to the hairs beneath ; elsewhere the pubes- 

 cence is black, but specimens in whicli the ochraceous predominates 

 sometimes show a j)ale floccus. I suspect that .4. errant Sm. is only 

 a variety of this species. 



Andrena erytlirogaster Ashmead ; C'ilissn erythrogasier Ashmead, Bull. 

 Col. Biological Association i, (i, 1890; A. peresi Rob., Trans. Am. Ent. Soc. 

 xviii, 51. 



Andrena pruni Rob., Trans. Am. Ent. Soc. xviii, 51. 



The male of this species closely resembles that of ..4. sayi. It is 

 distinguished by its somewhat smaller size, clearer wings, the abdo- 



