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



the sides of the fore-chest are notched : the legs are rather short ; 

 the fore-legs are but little shorter than the hind-legs ; the wings 

 are somewhat small ; the main vein widens into the brand a little 

 beyond the middle of the fore-border of the wing ; its inclina- 

 tion inwards and outwards is very slight ; the brand is very pale 

 yellow, irregularly spindle-shaped, and forms a very obtuse angle 

 along its hind-border ; the branch-veins are slightly curved, and 

 very slender except at the base ; the third vein is distinct at its 

 source, it is forked a little beyond one-third, and forked again a 

 very little beyond two-thirds of its length ; the fourth is very 

 short ; the first vein is perpendicular to the main vein. The third 

 vein sometimes sends forth its forks a little before one-third and 

 two-thirds respectively of its length. 



It is infested by an Aphidius and by an Allotria. 



The oviparous wingless female. This appears in the beginning 

 of August, and sometimes does not disappear before the middle 

 of October : the body is nearly elliptical, and sometimes all yel- 

 low, but more often the middle chest is brown, and there is a 

 broad brown band across the abdomen whose tip is slightly 

 lengthened : the limbs are yellow ; the feelers are not half the 

 length of the body : the hind-shanks are broad, and there is a 

 black spot at the tip of each thigh. 



The winged male. Like the winged female, but more slender : 

 the sides of the body are almost black : the head and the middle 

 chest are brown, and there are four brown spots on the back of 

 the abdomen : the veins of the wings are more distinctly marked 

 than in the female, and the wing-brands are darker and shaded 

 at both ends : the feelers are yellow, and very nearly as long as 

 the body ; the first and the second and the tips of the following 

 joints are brown : the tips of the hind-thighs and the base of the 

 hind-shanks are slightly clouded : there is a small brown spot 

 at the tip of each thigh : the tips of the feet are black. 



1st variety. The hind-thighs and the hind-shanks are black, 

 excepting the base of the former and the tips of the latter. 



2nd variety. The sides of the abdomen are brown, and there 

 are two spots of the same colour in a line on its back. 



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



16. Aphis Platanicola. 



Lachnus Platanicola, Kalt. Mon. Pflan. i. 



The species is not a native of England, and the following notes 

 are taken from specimens given to me by Professor Kaltenbach 

 of Aix-la-Chapelle, in whose work on Aphides it is more fully 

 described. Perhaps it should form part of the following group. 



The viviparous winged female. The body is orange, and rather 

 broad ; the abdomen is black : the feelers are yellow at the base, 



