164 



Zoology of Colorado 



wild plants in the mountains, and are not regarded as harmful. 

 Many live on conifers, and have recently been made known with 

 beautiful colored illustrations by Professor Gillette and Miss M. 

 A. Palmer.* Tamalia coweni Cockerell produces red galls on 

 the leaves of kinnikinnick and on the related manzanita in Cali- 

 fornia. Species of Pemphigus and related genera make galls on 

 poplar or cotton wood trees; one of the commonest is P. populi- 



Plant Lice (Myzus ribis Linnaeus) after Gillette, Journ. Economic Entomology 1917. Much 

 enlarged. This species is injurious to currants. Drawn by Miss Palmer 



monilis Monell on narrow-leafed cottonwood. Gilleitea cooleyi 

 Gillette makes galls on silver spruce, and migrates to the Douglas 



*Annals Entomological Society of America, XVII. (1924) No. I. 



