GENERIC CLASSIFICATION OF APHIDIDAE. 45 



short, subcylindrical ; cauda somewhat conical, not quite as long as the cornicles; anal 

 plate rounded. Tarsi atrophied in all the forms. 



Type (mono typical), Atarsos grindeliae Gill. 



Genus BRACHYCOLUS Buckton. 



Plate VI, T, IT. 



1879. Brachycolus Buckton, Mon. British Aphides, v. 2, p. 146. 

 1913. Brachysiphum Van der Goot, Tijd. voor Ent., v. 56, p. 105. 



The genus Brachycolus was erected with stellariae Hardy as type 

 and is easily recognized from the structure of the cornicles. Van 

 der Goot's genus is in all essential respects the same, the type of that 

 genus being thalictri Koch. 



Characters. — Head without prominent antennal tubercles. Antennae of six segments 

 and armed with subcircular sensoria. Wing venation normal. Cornicles very small, 

 especially in the apterous form. Cauda medium in size and conical. Body elongate; 

 legs and antennae usually short. 



Type (monotypical), Aphis stellariae Hardy. 



Genus BREVICORYNE V. d. Goot. 

 Plate VI, J, K. 



1915. Brevicoryne Van der Goot, Beitrage z. Kennt. d. Holl. Blattlause, p. 245. 



1916. Oedisiphum Van der Goot, Zur Kenntniss der Blattlause Java's, p. 122. 

 1918. Brevicoryne Das, Mem. Ind. Mus., v. 6, p. 179. 



The genus Brevicoryne was erected with Aphis hrassicae L. as type, 

 a species in which the cornicles are very short and somewhat swollen 

 in the middle, and the cauda conical. In the species Oedisiphum 

 compositarum V. d. Goot quite similar characters are found. The 

 cornicles appear to be somewhat more slender but in the main the 

 species appear alike. Oedisiphum, therefore, becomes a synonym. 



Characters. — Head without prominent antennal tubercles; antennse of six segments 

 and armed with subcircular sensoria. Wing venation normal. Cornicles short, not 

 much longer than the cauda and swollen in the middle. Cauda short and broadly 

 conical. 



Forms not especially elongate. 



Type (monotypical), Aphis hrassicae L.. 



Genus CAROLINAIA Wilson. 



Plate VI, V, W. 

 1911. Carolinaia Wilson, Can. Ent., v. 43, p. 61. 



The genus Carolinaia Wilson is related very closely to Rhopalosi- 

 phum. In fact some of the species placed here are distinguished 

 from members of that genus only by the fact that the cubitus is 

 lacking in the hind wing. It is true that the type species was 

 described as having five-segmented antennas in the apterous form. 

 But other species, like this in all other respects, have normal six- 

 segmented antennse. Certain species of Rhopalosiphum will show 

 strains in which nearly all of the individuals will have five-segmented 

 antennas and yet the normal antenna for such species is a six- 

 segmented one. In this closely related genus, therefore, it is not 

 surprising if a similar condition is met with. 



