1042 LIST OF HOMOPTEROUS TN8ECTS. 



as the fifth ; seventh a little longer than the sixth : front convex in 

 the middle with a slight tubercle on each side : eyes dark piceous, 

 prominent : legs slender, rather short ; fore-legs but little shorter 

 than the hind legs ; shanks straight : nectaries less than one-twen- 

 tieth of the length of the body. On the Birch. Length | line. 



England. 



315. Aphis impingens. 



Flava, depressa, subovata ; antenna corporis quadrante breviores ; 

 cornicula nulla ; pedes breves, validi. 



The viviparous wingless female. Body yellow, rather flat, in- 

 creasing in breadth from the head till near the tip of the abdomen : 

 head forming a half circle, rounded in front : eyes piceous, on the 

 top of the head, not on the sides as is usual : feelers not one-fourth 

 of the length of the body; first and second joints short; fourth 

 much shorter than the third ; fifth and sixth of moderate length ; 

 seventh very short : mouth not reaching much beyond the fore-hips ; 

 fore-chest moderately large ; sides convex ; nectaries not rising 

 above the surface of the abdomen : legs short, rather stout ; fore- 

 legs seated some way in advance of the fore hinder legs : abdomen 

 rounded behind. On the Birch. Length of the body f line. 



England. 



316. Aphis diphaga. 



Aptera. Parva, ovata, convexa, obscure" flava, viridi varia; an- 

 tennm flava, apice nigra?, corpnre paullb longiores ; cornicula 

 viridia, corporis quadrante vix breviores ; pedes longi, flavi, 

 tibiis apice tarsisque nigris. 



Alata. Nigra vel nigro-fusca, nitens, linearis, pedes flavi ; femoribus 

 tibiisque apice tarsisque nigris ; alee limpida. 



The viviparous wingless female. Small, oval, convex, smooth, 

 not shining, pale yellow, and mottled with green : feelers pale yel- 

 low with black tips, a little longer than the body : mouth pale yel- 

 low with a black tip : nectaries dark green, about one-fourth of the 

 length of the body: legs long, pale yellow; feet and tips of the 

 shanks black. 



