The Zoologist — January, 18G8. 



1049 



A. Winged form obvious or at least known. 



a. Culiital vein twice-forked. 

 aa. Cubital vein once-forked or simple. 

 AA. Winged form unknown. . 

 AAA. Antennae five-jointed or three-joiuted. 

 A. Winged form unknown. . 

 A A. Winged form obvious or at least kmwn. 



2. Lachnin.e. 



3. FOMl'HIGINiE. 



4. Rhizobiin/e. 



5. Tyohein^;. 

 6. ChebmessinjE. 



1. Aphidin^e, Passer int. 

 A. Antennas on a frontal tubercle. 



A. Antenna? closely approximate at the base. Front grooved. 1. Siphonophora. 

 AA. Antenna? remote at the base. Front flat or convex. 



a. First joint of the antennae with a tooth on the inner side. . 2. Phorodon. 

 aa. First joint of the antennae not toothed. 



a. Nectaries evidently clavate 3. Rhopalosiphum. 



aa. Nectaries cylindrical, sometimes hardly attenuated at the base [Myxut 

 Ribis), more often incrassated. 



* Cubital vein twice-forked. 



t Tail much shorter than the nectaries 4. Mtzus. 



ft Tail longer than the nectaries, rarely equal to them in length. 



5. HVALOPTEEUS. 



** Cubital vein once-forked 6. Toxoptera. 



AA. Antenna? not on a tubercle. 



A Seventh joint of the antenna? longer or at least as long as the sixth. 

 a Antenna? smooth. 



a. Nectaries longer than thick ; or if shorter or none, then the apterous 

 viviparous female with a smooth back. 



* Nectaries cylindrical, very rarely none (A Gallarum). . 7. Aphis. 

 ** Nectaries elavate. 8. SipuocoRyNE. 



aa. Nectaries shorter than thick ; or if a little longer than the viviparous 



apterous female, aud the pupa with a hairy back. . 9. Myzocallis. 

 aa. Antennae pilose. 



a. Nectaries cylindrical, at least twice longer than thick. . 10. Cladobius. 

 aa. Nectaries tubercle-shaped, much shorter than thick, sometimes almost 

 on a level with the surface. 

 AA. Seventh joint of the antennae shorter than the sixth. 

 a. Aerial species. Winged form very elegant. 

 aa. Subterraneous species. Winged form unknown. 

 a. Third joint of the antennae longer than the fourth 

 one joint. ...... 



aa. Third joint of the antenna? as long as the fourth 

 jointed. 



11. Chaitophorcs. 

 12. Pterocallis. 



Hind tarsi with 



. 13. Teama. 

 Hind tarsi two- 



. 14. Paracletus. 



Genus 1. Siphonophora, Koch. 



Typical species, Aphis Rosa, Linn. — Antennae on a frontal tubercle, 

 longer than the body ; seventh joint setaceous, longer than the sixth. 



SECOND SERIES— VOL. III. E 



