A SYNOPSIS OF THE APHIDIDAE 89 



16. Cauda shorter than hind tarsi. Ill with 11 to 15 sensoria scattered irregu- 



larly along segment (fig. 294) marutae Oestlund 



Cauda longer than hind tarsi. Ill with 5 to 9 more or less evenly arranged 



sensoria viburnicolens n.sp. 



17. Cornicles equal to or longer than III 18 



Cornicles not as long as III 19 



18. Cauda, cornicles, and III subequal. Second branch of third discoidal vein 



very near to apex of wing spiraecola Patch 



Cauda considerably shorter than cornicles or III, the last two being subequal. 



Second branch of third discoidal about midway between base of first 

 branch and apex of wing oenotherae Oestlund 



19. Fore wing with the second branch of the third discoidal arising very near 



to the apex of the wing. (In a few cases the second branch is not found, 

 but never in both wings) (fig. 191) avenae Fabr. 



Venation of fore wing normal (fig. 187) 20 



20. Antennae longer than body persicae-niger Smith 



Antennae not longer than body 20 



21. A pair of small tubercles present on the middle of the seventh and eighth 



abdominal segments malifoliae Fitch 



Such tubercles not present 22 



22. V with secondary sensoria. VI spur longer than III 23 



V without secondary sensoria. VI spur at most equal to III 25 



23. Beak scarcely reaching second coxae maidis Fitch 



Beak reaching beyond second coxae, even to or beyond the third 24 



24. Cornicles longer than cauda (figs. 194, 195) and more than twice as long as 



hind tarsi sambucifoliae Fitch 



Cornicles and cauda subequal; the former not more than twice as long as 



hind tarsi neomexicana Cockerell var. pacifica Davidson 



25. Cauda and hind tarsi subequal. Ill with a few large sensoria (fig. 232). 



Abdomen green with dark dorsal markings ramona Swain 



Cauda longer than hind tarsi. Ill with several sensoria. Abdomen black 



or dark brown 26 



26. Cornicles more than twice as long as hind tarsi, often almost three times as 

 long. VI spur and cornicles subequal, hind tarsi and. VI base subequal. 



hederae Kalt. 



Cornicles never more than twice as long as hind tarsi, usually considerably 



less. Hind tarsi usually slightly longer than VI base, and VI spur longer 

 than cornicles euonomi Fabr. 



27. Cornicles distinctly knobbed, the tip being widened to twice the width of 



the rest of the cornicles frlgidae Oestlund 



Cornicles normal 28 



28. Fore wing with the second branch of the third discoidal arising very near the 



apex of the wing (fig. 188) salicicola Thomas 



Fore wing with venation normal (fig. 187) 29 



29. Cornicles distinctly longer than cauda 31 



Cornicles at most equal to cauda 30 



30. Cornicles short and swollen throughout apical one-half (fig. 203). Antennae 



as long as or longer than the body . brassicae Linn. 



Cornicles short and slender, and slightly clavate on one side. Antennae 



scarcely two-thirds as long as the body atriplicis Linn. 



31. Abdomen without lateral tubercles on anterior segments. Cauda short and 



broad, with rounded tip, and almost as long as the cornicles cardui Linn. 



Abdomen with lateral tubercles on at least one of the anterior segments .... 32 



