10 POMONA JOURNAL OF ENTOMOLOGY 



shaped terminal surrounded by several marginals in the process. Abdomen — 

 deeply segmented. (Figure 7.) 



Nymph of Viviparous Apterous Female. — These young are about one- 

 tenth as large as the adultj and resemble them in most respects. 

 The body is very hairy. The antennae (Figure 5, F) are longer than the body, 

 very hairy, four-jointed, 0.53 mm. long (nearly as long as in adult), with 

 an apical nail-like process on last article. The comparative lengths of the 

 articles are as follows: I 0.05 mm., II 0.09 mm., Ill 0.19 mm., IV 0.19 mm. 

 The sensoria are distributed as follows: I and II none, III one large circular 

 near distal end, IV one large cup-shaped terminal surrounded by several mar- 

 ginal in process. Rostrum — longer than body. Abdomen — slender compared 

 with adult. 



This aphid was first taken at Santa Paula, Calif., Nov. 1, 1908, where 

 it occured in considerable numbers on the roots of Amaranthus retroflexus. 

 At Claremont it occurs in great numbers on the roots of Solanum douglasii. 

 For several months I was unable to obtain winged specimens, which led me 

 to place it in the genus Tychea. Late in January were obtained the winged 

 form which showed it to belong to the genus Pemphigus. 



