Pomona CoLLiiciK Journal of Entomology 399 



(vivipara) is dark brown with a median dorsal yellow line. It has the 

 hairs and other characteristics of the tjenus Chaitophorus. On Sali.r spp. 



Chaitophorus populifoliae Fitch 

 The specimens agree with Oestliind's description of this species. Mr. j. j. 

 Davis writes me that he is certain Oestlund's specimens are not the same 

 as those described by Fitch. Both alate and apterous viviparae occured com- 

 monly on Popuhis fremontii Wats. 



Callipterus quercus Kalt 

 This is the same insect that I listed under this name in the Journal of 

 Economic Entomology Aug. 1910, p. 367. I cannot compare it satisfactorily 

 with any native Callipterus, while it compares favorably with Buckton's 

 description of C. quercus. I have taken specimens of this insect in the Santa 

 Clara valley on the under side of the leaves of Quercus lobata Nee, Q. cali- 

 fornica Cooper, Q. douglasii H. and A., and on an imported English oak, 

 Quercus robur (?). It seems to attack the last-named more scvcreh than 

 the others. On Q. lobata Nee, in Placer County. 



Aphis brassicae Linn 

 On cabbages, uncommon. 



Aphis lutescens Monell 

 This bright yellow insect was observed in abundance on the stalks and 

 hoods of Asclcpias mcxicana Cav. 



Siphocoryne conii Davidson 

 The Placer County specimens are identical with those taken at Palo Alto 

 on Conium maculatum L. and described by me in the Journal of Economic 

 Entomology, Aug. 1909. The insect is rare in Placer County. Its food- 

 plant is an umbelliferous plant which I have been vmable to identify. 



Rhopalosiphum dianthi Schrank 

 Common on Sonchus oleraceus L. In the Santa Clara valley both this 

 species and Macrosiphum sonchella Monell are found commonly on sow- 

 thistle, sometimes together on the same specimen of food plant, but in Placer 

 County I failed to find the latter species although I examined considerable 

 numbers of the food-plant. 



Macrosiphum californicum Clarke 



Common on the tips of willow shoots where they cause the shoot to curl. 

 They prefer the yoimg stem growth to the leaves. 



Macrosiphum rosae Ream 

 Fairly common on cultivated roses. 



