14 



Rev. T. A. Marshall's Monograph of 



Table of Genera. 



(2) 1. Prsediscoidal areolet separated from the 

 1st cubital by a nervure which is often 

 partially, but never wholly, effaced ... 



Prrediscoidal areolet not distinct from 

 the 1st cubital 



No intercubital neivures ; the single 

 cubital areolet extends to the tip of 

 the wing 



Intercubital nervures more or less dis- 

 tinct ; 3 cubital areolets 



Abdomen lanceolate, subsessile; an- 

 tenuse 11-jointed in both sexes 



Abdomen orbicular, subpetiolate ; an- 

 tennse with more than 11 joints 



Abdomen orbicular 



Abdomen lanceolate 



Antennfe 10-13-jointed ; ventral valve 

 of the 9 furnished with two setiform 

 apical appendages, longer than the 



terebra 



(9) 10. Antennae with more than 13 joints 

 (rarely with 11, 12, or 13 joints, in the 

 most minute of the genus Aphid his) ; 

 ventral valve of the ? without appen- 

 dages ■■■ 



Q2) 11. Head transverse, not produced behind 

 the eyes ;' cheeks not dilated ; anal 



nervure interstitial 



(11) 12. Head longer thau broad, much produced 

 behind the eyes ; cheeks dilated ; anal 

 nervure springing from the middle of 

 the extremity of the podiscoidal 

 areolet 



3 



7 



Praon. 

 5 

 Ephkdrus. 



TOXAEES. 

 MONOCTONDS. 



V. Teioxts. 



11 



Aphiditjs. 



vii. Dtscritu.s. 



I. PRAON, Haliday. 

 Hal, Ent. Mag., i, 483 (1833). 

 Head subglobular, flattened anteriorly ; maxillary palpi 4-, labial 

 3-jointed ; mandibles deeply bidenticulate. Antennae with a variable 

 number of joints, always greater in the males. Mesothoracic furrows 

 distinct ; thorax somewhat downy. Prsediscoidal areolet separated 

 from the 1st cubital by a nervure more or less indistinct ; podis- 

 coidal widened exteriorly : no intercubital nervures, the radial 

 nervure forming no angles, the single cubital areolet extending to 

 the tip of the wing ; stigma triangular, short, but prolonged in a 

 fine line to the parastigma ; costal areolet of the hind wings closed. 

 Aljdomen of the $ almost sessile, lanceolate, shorter in the (^ , oval 

 sublinear, first segment short, the spiracular tubercles basal. Terebra 

 conical, horizontal or slightly curved upwards. 



This genus may be recognised (1) by the radial nervure, 

 which presents no vestige of the anastomoses giving 

 origin to the intercubital nervures ; (2) by the stigma, 

 which is shorter than in the other genera, but emits 

 a linear prolongation to the parastigma ; and (3) by the 



