Mr. F. Walker's Descriptions of Aphides. 329 



the base than towards the tips, and hardly more than one-fourth 

 of the length of the body ; the fourth joint is more than half the 

 length of the third ; the fifth is a little shorter than the fourth ; 

 the sixth is shorter than the fifth, and the seventh than the sixth : 

 the eyes are brown : the mouth is pale green with a brown tip : 

 the back is adorned with rows of black spots which become more 

 distinct towards the head : the nectaries do not rise above the 

 surface of the abdomen : the legs are dull pale green, and rather 

 short ; the knees and the feet are darker. It sheds its skin in 

 May, and is then paler, but as it grows it acquires a more vivid 

 green colour, and has occasionally three rows of black spots along 

 its back ; it now exudes more abundantly the white cottony mat- 

 ter wherein it soon becomes fully wrapped ; this secretion abounds 

 beneath the leaves, and being removed thence it changes into a 

 solid sugar or gum sweet to the taste and melting on the tongue. 

 When full-grown it is oval and flat, and has six rows of darker 

 spots along the back ; these spots are all confluent with the ex- 

 ception of the outer row on each side : the forehead is convex, 

 and without spines : the feelers are rather less than half the 

 length of the body ; the fourth joint is much shorter than the 

 third ; the fifth is a little shorter than the fourth, and the sixth 

 than the fifth ; the seventh is extremely short : the mouth extends 

 to the middle of the space between the fore-hips and the middle 

 hips. The body varies in shape ; sometimes it is long and nar- 

 row, sometimes it is comparatively short and broad. 



The viviparous winged female. The rudimentary wings are pale 

 yellow, and they are unfolded in the middle of May : the body 

 is then pale green, thickly clothed with white filaments : the disc 

 of the head and that of the chest are black, and the abdomen has 

 a black band across each segment, and a row of black spots on 

 each side : the feelers are black, slightly setaceous, and rather more 

 than half the length of the body : the mouth is pale green ; its 

 tip, the eyes, and the legs are black ; the latter are moderately 

 long ; the fore-thighs are pale green : the wings are colourless ; 

 the wing-ribs are pale green ; the wing-brands and the veins are 

 brown. It looks like a twist of cotton floating through the air, 

 and its down has sometimes a delicate and beautiful azure hue. 



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



The oviparous wingless female. This appears in October, and 

 is shining pale yellow or pale orange, which latter colour it may 

 owe to the eggs which it incloses : it has also sometimes a red- 

 dish tinge on each side which is adorned with a row of black dots, 

 and frequently there is also a row of short black or gray bands 

 along the back of the abdomen. The eggs are fastened in 

 November to the twigs of the beech-tree ; when newly laid they 

 are yellow, but they soon become black. 



