Mr. F. Walker^s Descriptions 0/ Aphides. 273 



at the base, and rather more than half the length of the body ; 

 the knees and the tips of the shanks are black. When still older 

 it acquires a green tint, especially on the abdomen : the nectaries 

 have black tips, and they are one-sixth, one-eighth or one-twelfth 

 of the length of the body : when full-grown the body is green 

 and spindle-shaped, and the abdomen is lengthened towards the 

 tip : the hind- shanks are hardly thicker or darker than the 

 others. 



1st var. Dark green with a bluish black hue. 



2nd var. Buff. 



3rd var. Pale orange. 



4th var. Pale red. 



5th var. The body is pale yellowish green, whitish green 

 beneath : the head is brownish : the feelers are about half the 

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

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

 length of the body : the legs are yellow ; the knees, the feet, and 

 the tips of the shanks are black. 



The winged male. It pairs with the oviparous female at the 

 end of October, and is black : the front and the rear of the fore- 

 chest, the fore-breast and the abdomen are dull yellow; the latter 

 is slightly traversed by black bands : the feelers are very nearly 

 as long as the body, and like those of the female are thick, with 

 the exception of the last joint ; the fourth joint is about half the 

 length of the third ; the fifth is very nearly as long as the fourth ; 

 the sixth is a little shorter than the fifth ; the seventh is rather 

 longer than the third : the mouth is dull yellow with a black tip : 

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

 yellow ; the feet and the tips of the thighs and of the shanks are 

 black : the wing-ribs are pale yellow ; the veins and the wing- 

 brands are pale brown ; the second fork is sometimes wanting. 



1st var. The mouth is black ; its base is dull yellow : the foiu* 

 hinder thighs are black, with the exception of the base. 



2nd var. The thighs are black excepting the base. 



Length of the body ^-| line ; of the wings 1^-2^ lines. 



In the beginning of November the winged female is still occu- 

 pied with bringing forth young ones, while the oviparous female 

 is laying eggs. The leaves of the mountain ash are sometimes 

 crowded with this Aphis in the autumn, and the wind carries 

 them away with their insect-load. The apple-trees sometimes 

 put forth new blossoms soon after the middle of June, the earlier 

 fiowers having been much injured by this Aphis and by Psylla 

 Pyri. Mr. S{)ence mentions that the abundance of Aphis mali 

 caused the failure of the apple crops in Worcestershire, Devon- 

 shire, and Herefordshire, in 1838. 



Ann. a^ Mag, N. Hist. Ser. 2. VoLy. 18 



