yjb LIST OF HOMOPTEBOUS INSECTS. 



the tip of the fourth vein is to the tip of the rib-vein ; length of the 

 third vein before the first fork generally much longer, sometimes a 

 little shorter than its length between the forks ; distance between 

 the tip of the rib-vein and the tip of the fourth nearly twice that be- 

 tween the tip of the fourth and the tip of the third vein. 



Var. Angle of the rib-vein beneath the brand less obtuse, and 

 its outward side shorter in one wing than in the other. 



a — rf. England. (In Canada Balsam). From Mr. Walker's collection. 



Group 2. Walk. Ann. Nat. Hist. Ser. 2, i. 255. 

 3. Aphis Betul^. 



Aphis Betula;, Linn. Si/st. Nat. ii. 735, 21. Faun. Sttec. 992. 



Bonnet, Hist. Nat. i. 3. RSaum. Ins. iii. pi. 22, f. 2. Deff. Ins. 



iii. 45, 3, f. 27, 28. Geof. Ins. Par. i. 496, 7. Fabr. Sp. Ins. 



ii. 386, 20. Maiil. Ins. ii. 316, 25. Ent. St/st. iv. 215, 25. 



Syst. Rhyn. 297, 25. Gmel. Ed. Si/st. Nat. i. 4, 2206,21. 



Ene. MUh. Hist. Nat. Ins. pi. 1 16, f. 9. Schrank, Faun. Boic. 



ii. 1 , 107, 1 189. Berk. Si/n. i. 120. Stew. El. Nat. Hist. ii. 1 1 0. 



Turl. Syst. Nat. ii. 705. Kalt. Mon. Pflan. i. 144, 118. 



Walk. Ann. Nat. Hist. Ser. 2, i. 255, 3. 

 Aphis nigritarsis, Heyden, Mus. Senkenburg, ii. Heft. 3, 299. 



Kalt. Mon. Pflan. i. 135, 103. Ratz. Forst. Ins. iii. 218, 20. 

 Aphis punclipennis ? Zetterstedt, Faun. Lapp. i. 559, 4. l?ts. Lapp. 



ii. 2, 311,7. 

 Nigritarsifex, Amyot, Ann. Sac. Ent. Fr. Zme Sirie, v. 480. 



The viviparous winged female. This, before the end of March, 

 is nearly elliptical, plump, bristly, very dark green, or almost black 

 above, but paler beneath : six rows of tubercles along the back : 

 mouth reaching ii little beyond the hind legs : feelers less than half 

 the length of tlie body : legs rather short and stout. As it increases 

 in size it becomes dark green, with the exception of the tubercles. 

 Fore-legs not much shorter than the hind-legs : rib slightly inclined 

 towards the fore-border at two-thirds of the length, and receding 

 from it beneath the brand, where it forms a distinct very long ob- 

 tuse angle; this begins very shortly after the middle of the fore bor- 

 der, is about one-third of the wliole length of the wing, nearly linear, 

 except at the tip, where it forms a long acute angle ; first, second, 

 and third branch-veins obsolete before their source, especially the 

 third vein, whose first fork begins at a little before one-third of its 



