A SYNOPSIS OF THE APHIDIDAE 113 



Alate viviparous female. Prevailing color pale to olive green. 

 Head and prothorax dark olive green, thoracic lobes almost black. 

 Abdomen pale green with marginal spots and patch on dorsum dusky. 

 Legs pale except tarsi, apex of tibiae, and apical two-thirds of femora. 

 Antennae, cornicles, and cauda dusky. Beak pale at base and dusky 

 at tip. 



Head (fig. 293) not quite as long as broad, with a prominent 

 tubercle at apex of front and small but distinct projections from head 

 on inner side of first antennal segments. Antennae about same length 

 as body or slightly longer or slightly shorter (figs. 294-295). Ill and 

 the spur are about equal or III slightly longer, never shorter than 

 spur. IV about one-half as long as III. V either shorter or equal to 

 IV. VI shorter than V and about one-third as long as spur. I and II 

 subequal and slightly shorter than VI. The usual primary sensoria 

 are present on V and VI and the accessory sensoria on VI. Ill is 

 tuberculate and IV is slightly so. IV has from two to six small, 

 circular secondary sensoria and III from eleven to fifteen irregularly 

 placed (fig. 294). The beak reaches considerably beyond the second 

 coxae, in some cases almost to the third. 



The prothorax is without lateral tubercles. The wings are about 

 twice as long as the body with normal venation. The stigmal vein is 

 curved its entire length, the second branch of the cubitus arises about 

 midway between the tip of the wing and the base of the first branch. 



The abdomen is without lateral tubercles in so far as the author 

 can discern. The cornicles (fig. 299) are short and taper slightly 

 from base to apex. They are about equal in length to the third tarsi, 

 are almost one-half as wide at base as long, and about one-third 

 as wide at apex as long. The cauda (fig. 298) is short and blunt 

 (conical) and about two-thirds as long as the cornicles. The anal 

 plate is half-moon-shaped and dusky at its distal edge. 



Measurements (of specimens in Canada balsam) : Body length, 

 0.918 to 1.02 mm. (av. 0.9248 mm.) ; width (thorax), 0.34 to 0.442 mm. 

 (av. 0.4082 mm.) ; antennae total, 0.885 to 1.02 mm. (av. 0.942 mm.) ; 

 I, 0.034 to 0.051 mm. (av. 0.037 mm.) ; II, 0.034 to 0.051 mm. (av. 

 0.048 mm.) ; III, 0.225 to 0.2975 mm. (av. 0.2601 mm.) ; IV, 0.117 to 

 0.17 mm. (av. 0.152 mm.) ; V, 0.1105 to 0.136 mm. (av. 0.1346 mm.) ; 

 VI, 0.068 to 0.102 mm. (av. 0.0833 mm.) ; spur, 0.204 to 0.272 mm. 

 (av. 0.2295 mm.) ; cornicles 0.0850 to 0.119 mm. (av. 0.0978 mm.) ; 

 cauda, 0.0595 to 0.068 mm. (av. 0.0624 mm.) ; hind tarsi, 0.085 to 

 0.102 mm. (av. 0.0901 mm.) ; wing length, 1.921 to 1.955 mm. (av. 

 1.928 mm.) ; wing width, 0.661 mm.; wing expansion, 4.556 mm. 



