274 Mr. F. Walker’s Descriptions of Aphides. 
78. Aphis Padi, Linn. 
Aphis Padi, Linn. Syst. Nat. 1. 734. 8; Faun. Suec. 981 ; 
Fabr. Ent. Syst. iv. 220. 50; Reaum. Ins. ii. pl. 28. fig. 9, 10; 
Schrank, Faun. Boic. 11. 115. 1216; Stew. El. u. 110; Turt. u. 
708 ; Kalt. Mon. Pflan. 1. 74. 53. 
Padifex, Amyot, Ann. Soc. Ent. Fr. 24 série, v. 477. 
The viviparous wingless female. This Aphis feeds on Prunus 
Padus, is hatched before the middle of March, and is then dull 
green: the feelers are blackish green, and less than half the 
length of the body: the eyes are dark brown: the mouth is 
dull green with a darker tip, and reaches the hind-hips: there 
is a dull red spot on each side of the abdomen near the nectaries, 
which are almost black, and about one-tenth of the length of the 
body: the legs are blackish green. In April it becomes rather 
broad, oval and convex, increasing in breadth from the head till 
near the base of the nectaries; its colour is now pale green, or 
grass-green tinged with yellow ; the red spot at the base of each 
nectary is larger than before ; and it is quite filled with young 
ones, and even the fore-chest is occasionally occupied by these 
little embryos, which sometimes exceed thirty in number: the 
feelers are pale yellow with brown tips, and not more than one- 
fifth of the length of the body; the fourth joint is more than 
half the length of the third; the fifth is very nearly as long as 
the fourth; the sixth is more than half the length of the fifth ; 
the seventh is more than twice the length of the sixth : the eyes 
are black: the forehead is prominent in the middle, and has a 
slight tubercle at the mner base of each feeler: the mouth is 
yellow with a brown tip, and reaches the middle-hips: the legs 
are yellow; the feet and the tips of the shanks are black; the 
four hinder shanks are slightly curved; the fore-legs are but 
little more than half the length of the hind-legs: the nectaries 
are yellow with brown tips, and about one-twentieth of the length 
of the body: there is a short tube at the tip of the abdomen. 
Before the end of April the mother of a colony gives birth to a 
progeny of young ones that are very unlike their parent, being 
much darker and of a blackish green colour, and covered with 
white powder which increases in quantity as they advance in age. 
The colour when the skin has been lately shed is sometimes pale 
orange or dull olive-green, with a pale green head and almost 
white limbs. Mr. Hardy has sent me this species from the 
neighbourhood of Berwick in July, but it disappears from the 
bird-cherry near London in the beginning of summer, when the 
foliage is often almost destroyed by it and by Yponomeuta Padella, 
and it does not return to that tree till the autumn. 
