186 Proceedings of the Biological Society of Washington. 



that brevis must become a synonym of crataegefoliae. The dis- 

 tinction of these species from bakeri given by Miss Patch is con- 

 firmed by the types of these two workers. 



Sanderson was evidently led astray by the referring of Fitch's 

 name to quite a different species closely related to if not identi- 

 cal with prunifoliae Fitch. 



A study of crataegefoliae shows that it is not an Aphis but 

 belongs to the genus Anur aphis as does also its close relative 

 bakeri. Indeed, there is a group of American species in this 

 genus having finely imbricated cornicles, the imbrications cov- 

 ered with minute points. Of this group crataegefoliae and bakeri 

 live upon rosaceous plants and migrate to clovers during the 

 summer. These two species will stand as follows : 



Anuraphis crataegefoliae (Fitch). 



Aphis crataegefoliae Fitch, 1851. 

 Aphis brevis Sanderson, 1902. 



Anuraphis bakeri (Cowen). 



Aphis bakeri Cowen, 1895. 

 Aphis cephalacola Cowen, 1895. 



