446 Mr. F. Walker's Desanptions of Aphides. 



not more than one-twentieth of the length of the body. Beneath 

 the leaves of Populus alba, the white poplar, a little before the 

 middle of April. In the beginning of June when full-grown it 

 is pale green, varied with vivid green, and is hairy, oval, and 

 rather flat : the feelers are pale green, shorter than the body ; 

 their tips are brown : the eyes arc black : the mouth is pale green ; 

 its tip is brown : the nectaries arc very short : the legs are pale 

 green, and moderately long ; the feet and the tips of the shanks 

 are brown. 



There are often two interrupted brown lines along the back ; 

 these lines vary in breadth and distinctness, and sometimes occupy 

 the greater part of the back ; they occasionally occur only on the 

 head and on the fore-part of the chest. The young ones have 

 the front convex in the middle : the broods are less numerous in 

 this species than in the kinds with long nectaries : the little ones 

 before birth are of various sizes, and the smallest do not exceed 

 the size of the heads of the largest. 



The oviparous wingless female. In colour it resembles the vivi- 

 parous wingless female : the feelers are not more than one-half, 

 or sometimes than one-third, of the length of the body, which is 

 more or less lengthened towards the tip : the hind-shanks are 

 slightly dilated and of a rather darker colour than the other 

 shanks : the fore-chest, like that of the male, has a dark spot on 

 each side. Its eggs are three or four in number. 



The viviparous winged female. Black, and rather small : the 

 fore-border, the hind-border and the underside of the fore-chest 

 are dark green : the abdomen is green, and has an interrupted 

 black band across the back of each segment, and a line of black 

 dots along each side : the feelers are black, pale yellow towards 

 the base, and shorter than the body : the eyes are black : the 

 mouth is dull green : the nectaries are black, and hardly one- 

 twelfth of the length of the body : the legs are pale yellow and 

 moderately long ; the knees and the tips of the shanks are brown ; 

 the hind-thighs are black : the wings are colourless, and much 

 longer than the body ; the wing-ribs are pale yellow ; the wing- 

 brands and the veins are black, and the latter are slightly 

 clouded. 



] st variety. Smaller than the preceding : the abdomen and 

 the underside of the fore-chest are pale green : the feelers are pale 

 brown, pale green at the base, and a little shorter than the body : 

 the mouth is pale green with a black tip : the legs are pale green : 

 the wing-brands and the veins of the wings are brown. On 

 Populus alba, the white poplar, in the beginning of June. 



At the end of August it much resembles the male in colour, 

 and sometimes, as in that sex, the wing-brand extends beyond 

 the rib-vein which passes through it, and the zigzag line men- 



