WiUon-Vickery—Xist of Aphidddae, 
299 
Populus cillata. 
Pemphigus imaicus Cholodkovsky. 
Pemphigus mordwilkoi Cholodkovsky. 
Pemphigus nainitalensis Cholodkovsky. 
Populus coccinea, 
Asiphum pseudohyrsa Walsh. 
Populus deltoides=:P. monilifera. 
Aphis populifoliae Pitch. 
Asiphum pseudohyrsa Walsh. 
Chaitophorus populicola Thomas. 
Chaitophorus stevensis Sanborn. 
Mordwilkoja vagahunda Walsh. 
Pemphigus hetae Doane. 
Pemphigus hursarius Linnaeus. 
Pemphigus oestlundi Cockerell, - 
Pemphigus populi-ramulorum Riley, 
Pemphigus popuU-transversus Riley." 
Phylloxera popularia Pergande. 
Phylloxera prolifera Oestlund. 
Pterocomma salicti Harris. 
Schizoneura populi Gillette. 
ThecaMus populicaulis Fitch. 
Thecahius populi-conduplifolius Cowen. 
ThecaMus popuU-monilis Riley. 
Populus deltoides-angustifolia. ? 
Chaitophorus populicola Thomas. 
ThecaMus populi-monilis Riley. 
Populus fremonti. 
Aphis populifoliae Fitch. 
Asiphum pseudohyrsa Walsh. 
Chaitophorus populicola Thomas. 
Pemphigus oestlundi Cockerell. 
Pemphigus populi-ramulorum Riley. 
Pemphigus populi-transversus Riley. 
Phylloxera popularia Pergande. 
Phylloxera prolifera Oestlund. 
ThecaMus populicaulis Pitch. 
ThecaMus populi-monilis Riley. 
Populus graudidentata. 
Aphis populifoliae Fitch. 
Aphis populi-grandidentata Rafinesque. 
Arctaphis populi Linnaeus. 
Chaitophorus populifoliae (Oestlund) Davis. 
