Pomona College Journal of Entomology 



587 



It will be my .liiii to continually improve this first .irticlt' by adding descrip- 

 tions of new aphids, natural enemies and better means of artificial control. I 

 invite tlie aid of all growers and otlier interested parties and ask them to send 

 specimens wiiich have not been included here, and I sliall be glad to make any 

 determinations of j)lant lice, j)rovided they are shipped in large quantities with 

 the host plant in a strong box so that the natural color and body shape can be 

 studied in connection with the anatomical characters.* 



Aphis cookii n sp. 

 WINGED VIVIPAROUS i-E.MALE (Figure lyi A). 



1910 Aphis gossypii Glover-Essig, Pomona Jr. Ent. Vol. II., pp. SSS-SSt. 



Length of body not including style 1.75 mm., width of mesothorax 0.70 mm., 

 greatest width of abdomen 0.78 mm., wing expansion 7.20 mm., rather large and 

 robust form. 







Figure 191. Aphis cookii 



Prevailing Color — Dark gray or black witli a whitish flocculence which makes 

 it appear whitish. Head — Black or dark brown, nearly twice as wide as long, with 

 rather large antennal tubercles, but these are not at all prominent. Eyes — Very 

 dark red or brown, terete tubercles extending nearly at right angles to the eye- 

 surface. Antennae (Fig. I91, D) — On small frontal tubercles, not as long as 

 the body, reaching to the bases of the cornicles, very sparsely haired, dark 

 throughout, imbricated; lengths of articles: I, 0.08 mm.; II, 0.08 mm.; Ill, 0.35 

 mm.; IV, 0.22 mm.; V, 0.22 mm.; VI, 0.44. mm. (spur 0.3 mm.) ; total 1.39 mm. It 

 will be seen from the above that I and II are coequal. III longer than either IV 

 or V, but shorter than VI; IV and V coequal. The sensoria are distributed as 

 follows: Article III (Fig. 191, C, C) with from seventeen to twenty-eight large 



