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



slender, setaceous, hairy, and as long as the body ; the fourth 

 joint much shorter than the third ; the fifth is a little shorter 

 than the fourth ; the sixth increases in breadth from the base to 

 the tip, and is not half the length of the fifth ; the seventh is as 

 long as the sixth, and much more slender than the preceding 

 joints : the front of the head is nearly straight, and has no tuber- 

 cles : the tip of the mouth is brown, and reaches the middle hips : 

 the sides of the fore-chest are convex : the nectaries are about 

 one-twentieth of the length of the body : the wings are colourless ; 

 the veins and the wing-brands are pale brown; the rib-veins 

 widen into the brands which are irregularly spindle-shaped, and 

 form on the hind-border a scarcely perceptible angle from whence 

 springs the fourth vein ; the first and the second veins are nearly 

 straight; the third vein is slightly inclined inwards, and forms two 

 very obtuse angles where it throws off its forks ; the first fork 

 begins after one-third, and the second fork before two-thirds of 

 the length of the wing ; the two forks are sometimes much nearer 

 to each other in one wing than in the other : the legs are yellow, 

 and moderately long ; the shanks are very slightly curved, and 

 rather hairy ; the tips of the feet are brown. 



Length of the body \\ line ; of the wings 3 lines. 



July, on the oak, near London. 



Eleventh Group. 

 21. Aphis Aceris. 



Aphis Aceris, Linn. Syst. Nat. ii. 7361 ; Faun. Suec. 999 ; 

 Fabr. Syst. Ent. 735. 9 ; Sp. Ins. ii. 385. 10 ; Ent. Syst. iv. 211. 

 11 ; Syst. Rhyn. 295. 11 ; Gmelin, ed. Syst. Nat. i. 2208 ; Geoffr. 

 Ins. i. 495. 5 ; Reaum. Ins. iii. 281-350. t. 22. f. 6-10; Scopoli, 

 Ent. Cam. 137. 397; Enc. Meth. i. t. 116. f. 6; Rossi, Faun. 

 Etrusc. 260. 1372 ; Schrank, Faun. Boic. ii. 1. Ill ; Fonscolombe, 

 Ann. Soc. Ent. x. 173. 13 ; Kaltenbach, Mon. Pflan. i. 125 ; 

 Ratzeburg, Forst. Ins. iii. 218. 



Acerifex, Amyot, Ann. Soc. Ent. Fr. 2 me serie, v. 479. 



This species abounds on the different species of maple, such as 

 Acer Pseudo-platanus, the sycamore; A. Platanoides, the plantain- 

 like or Norway maple; A. campestre, the field maple ; A. opali- 

 folium, the guelder rose-leaved maple; A. Monspessulanum, the 

 Montpelier maple ; A. tataricum, Tartarian maple ; A. Negundo, 

 ash-leaved maple. 



The egg-born viviparous wingless female. It is hatched in the 

 middle of February or later, and is then very small, black, bristly, 

 linear, or slightly increasing in breadth towards the tip of the 

 abdomen : the limbs are short and thick : the mouth reaches a 

 little beyond the tip of the abdomen, a character retained through 



