590 Pomona College Journal of Entomology 



Aphis gossypii Glover 



1854 Aphis gossypii Glover, Pat. Off. Kept., p. 62. 



1882 Aphis citrulli Ashmead, "Florida Dispatch," vol. I, p. 2-il. 



1883 Aphis cucumeris Forbes, 12th Rept. Ent. 111., pp. 83-91. 



WINGED VIVIPAROUS FEMALE (Figure 192 A) 

 Length of body not including style 1.35 mm., width of mesothorax 0.42 mm., 

 greatest length of abdomen O.fiS mm., wing expansion SAO mm. Very small form. 

 Prevailing color — Dark, black or very dark green or brown. Head — Much 

 wider than long, black. Eyes — Very dark red or brown. Antennae (Fig. 192, c 

 and h) — Arising directly from the head, not as long as the body, reaching to the 

 bases of the cornicles, sparsely haired; articles I and II du.sky, III with light 

 base and remainder dusky, IV and V light yellow with apical halves dusky, VI 

 dusky throughout; length of the articles: I, 0.07 mm.; II, 0.04 mm.; Ill, 0.22 mm.; 

 IV, 0.17 mm.; V, 0.17 mm.; VI, 0.37 mm.; (spur 0.26 mm.) ; total 1.04 mm.; from 

 seven to eight large circular sensoria on article III (Fig. 192, h), remaining 

 article normal. Rostrum — Reaching to or slightly bej'ond third coxae, lemon yellow 

 with the base and tip dusky. Prothorax — Slightly wider than the head, but no 

 longer ; black, with distinct lateral tubercles. Meso- and Metathorax — Black, with 

 prominent muscle lobes. Abdomen — Smooth, dark green or greenish brown, with 

 an irregular lighter area on the dorsum, ventral surface dull green, small lateral 

 marginal tubercles extending from sides, anal plate (Fig. 192, a and b) dusky, 

 hairy. Cornicles (Fig. 192, g) — Cylindrical, wider at base and gradually tapering 

 to tip; imbricated, black, curved slightly outwardly in some specimens, length 

 0.2 mm. Legs — Normal, hairy, coxk black, femora of first and second pairs light 

 3'ellow, femora of third pair yellow with apical three-fourths dusky, tibiae yellow 

 with dark tips, tarsi dark. Wings — Rather large for the size of the species, 

 hyaline. Primary — Length 2.3 mm., width 0.95 mm. ; costal vein dark and well 

 defined ; subcostal wide, yellow ; stigma long and narrow, tapering from the base 

 of the stigmal vein to a point at the tip, amber in color, length 0.65 mm. ; first 

 discoidal straight, second discoidal curved inwardly toward the body, third discoidal 

 twice-branched and curved slightlj' inwardly, first branch arising near the middle 

 of the vein, the second branch arising nearer the tip than the middle of the first 

 branch — both of these branches curve toward the third vein. All veins are amber. 

 Primary — Length 1.5 mm., width 0.55 mm.; subcostal curved downwardly at the 

 base of the second discoidal and then curves upwardly to point of wing ; discoidals 

 nearly straight. Style (Fig. 192, a, dorsal, and b, ventral) — Conical or nearly 

 cylindrical, hairy, green, with dusky tip, length 0.11 mm. — a little more than half 

 as long as the cornicles. 



APTEROUS VIVIPAROUS FEMALE (Figure 192 B) 

 Length of body not including style 1.8 mm., width of abdomen 0.9 mm. Larger 

 than the winged form and more robust, although many are oblong in shape, not as 

 robust as the apterous forms of Toxoptera auraniiae Koch. Some slightly pruinose 

 giving them a gray color. 



