430 Mr. P. Walker's Descriptions of Aphides. 



the feelers are more than half the length of the body, whose seg- 

 ments are short, transverse, and nearly equal in size : the nec- 

 taries are about one-sixth of the length of the body : its colour 

 presents the following varieties : — 



1st var. The head is almost brown. 



2nd var. The body yellowish green. 



3rd var. The body bluish green. 



4th var. The body whose skin has been lately shed is light 

 delicate green, inclining to white towards the head : the limbs 

 are also white with the exception of the black tips of some of the 

 joints of the feelers. 



5th var. The body is deep green : the head is nearly yellow. 



As the insect grows, its body discovers a paler and brighter 

 green colour, and is less linear, and more convex, and shining, 

 the sutures between the abdominal segments become less di- 

 stinct, and the rim on each side of the abdomen is more conspi- 

 cuous. 



6th var. Yellow in front, deep green behind, having two rows 

 of dark dots along the body : the feelers are pale yellow ; their 

 tips are brown : the tips, of the nectaries are also brown : the 

 feet and the tips of the thighs and of the shanks are black. 



It also varies slightly in shape, and in the length of the 

 feelers, which are a little longer or a little shorter than the body. 

 The autumnal young are sometimes bright pale yellow, except 

 the nectaries, the feet, and the tips of the feelers, which are 

 black. 



The viviparous winged female. It is green : the head, the disc 

 of the chest, that of the breast, the feelers, the nectaries, the 

 feet, and the tips of the thighs are black : the wings are colour- 

 less ; the veins are brown. 



54. Aphis pallida, n. s. 



This species resembles A. Urticce in structure, but is very di- 

 stinct ; its colour is paler, especially in the winged form ; the first 

 joints of the feelers and the tubercles on which they are seated 

 are less developed : the wing-brands are almost white ; the first 

 and second veins are thicker and more distinct than the third 

 vein. 



It feeds on Calceolarias in greenhouses, on a Villarsia in hot- 

 houses, and on some other plants. 



The viviparous wingless female. The body is pale straw-colour, 

 shining, oval, and convex : there is a large pale green spot at the 

 base of each nectary : the feelers are much longer than the body ; 

 the tips of their joints, the eyes, and the tip of the mouth are 

 black : the nectaries are nearly as long as one- fourth of the body : 



