274 Mr. F. Walker's Descriptions 0/ Aphides. 



78. Aphis Padi, Linn. 



Aphis Padi, Linn. Syst. Nat. ii. 734. 8 ; Faun. Suec. 981 ; 

 Fabr. Ent. Syst. iv. 220. 50; lleaura. Ins. iii. pi. 23. iig. 9, 10; 

 Schrank, Faun. Boic. ii. 115. 1216; Stew. El. ii. 110; Turt. ii. 

 708; Kalt. Mon. Pflan. i. 74. 53. 



Padifex, Amyot, Ann. Soc. Ent. Fr. 2^^ serie, 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 inner 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. Ilardy 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. 



