402 



Pomona Collect: Journal of Entomology 



winged form (Fig. 140 B) ; I 0.156 mm., II 0.65 mm., Ill 1.01 mm., IV 0.65 



mm.. V 0.506 mm., VI 1.175 mm., (VI 0.165 and VII 1.01 mm.). Slightly 



hairy. Cornicles — Dark, length, 1.5 mm. Rostrum reaches mesothoracic coxse. 



Collected by the author from Ambrosia psilostachya and Baccharis viminca. 



Aphis lutescens Monell 

 Winged J'iviparous Female. (Fig. 141 A.) Length, 1.75 mm., width, 1 mm., 

 wing expansion. 7.7 mm. Prevailing color. — Lemon yellow, with dark thorax 

 and other dark markings as below described. Head — Narrower than thorax, 



Figure 1-11. Aphis lutescens: 

 A, Winged viviparous female; B, apterous viviparous female. 



light yellow in color. Byes — Dark, small. Antennae (Fig. 140 C) — Shorter than 

 the body, pilose. Lengths of articles are as follows: I 0.063 mm., II 0.045 

 mm., Ill 0.376 mm., IV 0.25 mm., V 0.188 mm., VI 0.47 mm. (VI 0.094 and 

 VII 0.376 mm.). There is a row of large circular sensoria on article III, 

 one on article V near the distal end, and several in the nail-like process of 

 article VI. There are few hairs on the articles. Prothorax with a small 

 lateral tubercle. Posterior half dusky in color. Rostrum — Reaches beyond 

 the metathoracic coxre. Dark at the tip. Abdomen — Smooth, bright yellow, 

 with margins spotted black as shown in drawing. Large black blotches 

 around the bases of the cornicles, one blotch between these blotches, one 

 behind this and a dark style. Three dark spots on dorsal surface of abdo- 

 men in front of the cornicles. Hairs on margins. Thora.v — Dark. Cornicles — 

 Cylindrical, dark, more than twice as long as the tarsus. Legs — Normal. 

 Dusky at the union of the femur and tibia, at the union of the tibia and 

 tarsus, the tarsus and also the claws. Slightly hairy. Wings — Normal as 

 shown in the cut. Veins yellowish brown as is also the long and narrow 

 stigma. Primary xvings — Length, 3.75 mm., width, 1 mm. Secondary zcings 

 — Length 1.8 mm., width, 0.4 mm. Style — About half as long as the cornicles, 

 dark, hairy. 



Apterous Viviparous Female. (Fig. 141 B). Length, 2 mm., width, 1.2 mm. 

 Prevailing color — Bright lemon-yellow throughout. Antennae — Resembles 



