Mr. F. Walker's Descriptions of Aphides. 201 



There are two varieties of this species on the willow, and they 

 differ in size ; the black colour predominates in the smaller va- 

 riety, and in the larger the green extends more over the body and 

 over the legs. The pupa? resemble the wingless insect in colour, 

 but the rudimentary wings and the disc of the chest are buff. 



The oviparous wingless female. It appears at the end of Octo- 

 ber, and is elliptical, dark velvet-like red, and rather flat : the 

 feelers are white with black tips, and about one-third of the 

 length of the body : the mouth is white ; its tip and the eyes are 

 black : the nectaries are white with black tips, and nearly one- 

 fourth of the length of the body : the legs are dirty white ; the 

 feet and the tips of the shanks are black ;_ the hind-shanks are 

 broad and grayish black. It continues sometimes till near the 

 end of November. 



1st var. Bright red : the disc of the abdomen is black. 



2nd var. The head is almost white. 



3rd var. Greenish yellow : the tip of the abdomen is orange : 

 the legs are pale green ; the hind-shanks are dull green. 



4th var. Orange colour. 



5th var. The body is dull yellowish green, flat, oval, not 

 shining : there is a broad irregular black stripe along the chest 

 whereon it divides and passes along each side of the abdomen : 

 the feelers are pale yellow, black towards the tips, and very nearly 

 half the length of the body : the mouth is pale ; its tip and the 

 eyes are black : the nectaries are white, and about one-twelfth of 

 the length of the body : the legs are dirty yellowish white ; the 

 feet and the tips of the shanks are black. 



The winged male. The body is small and black : the abdomen 

 is dark brown : the feelers are black, thick from their base till 

 near their tips, and nearly as long as the body : the mouth is 

 yellow with a black tip ; the nectaries are black, and about one- 

 sixth of the length of the body : the legs are black ; the shanks 

 except their tips are yellow : the wings are colourless and much 

 longer than the body ; the wing-ribs and the rib- veins are yellow ; 

 the brands and the other veins are brown. 



1st var. The abdomen is broad, and rather dark yellow ; the 

 nectaries are as long as the body : the legs are yellow ; the four 

 hinder thighs, excepting the base, the feet, and the tips of the 

 shanks and of the fore-thighs, are black. 



2nd var. The abdomen is very dark red beneath, and covered 

 with white powder : the feelers are a little longer than the body : 

 the nectaries are as long as one- eighth of the body : the legs are 

 black j the thighs are pale yellow at the base ; the shanks ex- 

 cepting their tips are dark yellow : the wing-brands arc pale 

 brown. 



3rd var. The body is pale greenish yellow : the head, the disc 



