GENERIC CLASSIFICATION OF APHIDIDAE. 19 



Characters. — Head slightly rounded; eyes large with, distinct ocular tubercles. 

 Antennae of six segments armed with large subcircular sensoria and thickly covered 

 with fine hairs. Cornicles situated on very broad, shallow, hairy cones. Cauda sub- 

 conical, slightly rounded. Anal plate rounded. Fore wings with radial sector rather 

 long and somewhat curved. Media twice branched; hind wings with both media and 

 cubitus present, quite widely separated. Beak very long, much longer than body. 

 Males wingless and with rudimentary mouth parts. 



Type (fixed by Walker, 1870), Aphis quercus Linn. 



Subtribe TRAMINA. 



The subtribe Tramina is composed of insects quite specialized in 

 nature, subterranean and often associated with ants. The typical 

 genus Trama is the most specialized of all and is in some- char- 

 acters suggestive of the Fordina. Its relations with the other 

 Lachnini, however, are shown clearly by the other genera. The 

 genus Trama, as described by Del Guercio (Redia, v. 5) possesses 

 small cornicles. Specimens of troglodytes, however, received from 

 Schouteden, Mordwilko, and others lack cornicles entirely. Some 

 other forms possess them either as very small cones or as large 

 Lachnus-like structures. These latter are evidently the most primi- 

 tive and to these is given the name Protrama. The insects with 

 small cornicles are grouped under the name Neotrama, The genera 

 may be separated as follows : 



Key to the Genera oe the Tkamina, 



1. Apterous form entirely without cornicles and with rudimentary eyes Trama. 



Apterous form with cornicles. .. . 2. 



2. Apterous form with large, broad, Lachnus-like cornicles and large distinct 



compound eyes Protrama. 



Apterous form with small cone-like cornicles armed with a few hairs and 

 more or less rudimentary eyes ISTeotrama. 



Genus PROTRAMA, n. gen. 

 Plate III, P-T. 



Head divided, front straight, eyes prominent and set off from the head. Antennae 

 of six segments armed with hairs and small subcircular protruding sensoria. Cornicles 

 situated on broad, low, hairy cones. Cauda and anal plate rounded. Hind tarsi 

 extremely elongate. Wing venation faint; fore wings with the media twice branched ; 

 hind wings with both media and cubitus present. 



Type, Trama radicis Kalt. 

 Genus TRAMA, Heydea. 



Plate III, N. 

 1837. Trama Heyden, Mus. Senfeb., v. 2, p. 293. 

 Head divided but not prominently so, front straight. Apterous form with the eyes 

 reduced to a few facets. Antennse of six segments; cornicles absent; caudasubconical, 

 rounded. Anal plate rounded. Entire insect minutely hairy. 



Type (mono typical;, Trama troglodytes Heyden. 



