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



El. ii. Ill ; Turt. ii. 706; Shaw, Gen. Zool. vi. pi. 58; Kalt. 

 Mon. Pflan. i. 72. 52. 



A. Pomi, Deg. Ins. iii. 36. pi. 3. fig. 18-21 ; Latr. Gen. Cr. 

 iii. 173. 



A. Oxyacantha, Schrank, Faun. Boic. ii. 116. 1219. 



Oxyacanthaphis, Amyot, Ann. Soc. Ent. Fr. 2 de serie, v. 478. 



This species feeds on Pyrus mains, P. communis, Cydonia vul- 

 garis, Mespilus germanica, Sorbus aucuparia, and Crataegus oocy- 

 acantha. 



When very young, and in the middle of March, it has a dark 

 green colour : the head and the limbs are still darker : the eyes 

 are dark brown : the feelers are half the length of the body : the 

 mouth reaches to the hind-hips : a dark stripe runs along each side 

 of the body : the nectaries are about one-eighth of its length : the 

 legs are rather short and stout : it dwells on the buds with the pale 

 orange young ones of Psylla Pyri. When full-grown it is green, 

 shining, oval, and convex: the limbs are brownish green : the feelers 

 are setaceous, rather stout, brown, pale green at the base, and less 

 than half the length of the body : the legs are pale green ; the 

 feet are brown : the front is broad and convex, and there are no 

 tubercles at the base of the feelers; the first and the second 

 joints of the latter are not angular ; the fourth joint is much 

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

 the sixth is a little shorter than the fifth ; the seventh is slender, 

 and rather shorter than the third. 



1st var. The body is pale yellowish green with three vivid 

 green stripes. 



2nd var. The body is grass-green, varied with yellow towards 

 the head : the limbs are pale yellow : the feelers are one-third of 

 the length of the body : the nectaries are one-twelfth of the length 

 of the body. 



3rd var. The body is green ; the limbs excepting the tips of 

 the feelers are paler. 



4th var. The body is green : the feelers are pale green, and 

 very much shorter than the body : the nectaries are green, and 

 from one-fourth to one-fifth of the length of the body : the mouth 

 is green ; its tip and the eyes are black : the legs are pale green 

 with brown feet. 



5th var. The feelers are shorter than the body, and the nec- 

 taries equal one-tenth of its length. 



6th var. The body is pale green : the feelers are pale brown, 

 pale green at the base, and rather more than half the length of 

 the body : the eyes are dark brown ; the mouth is pale green 

 with a darker tip : the nectaries are less than one-twelfth of the 

 length of the body : the legs are pale green, and rather short ; 

 the feet and the tips of the shanks are brown. 



