94 MAINE AGRICUIvTURAL liXPERIMENT STATION. I9I3. 



P. berolinensis. 



Pemphigus hursarius h. (lactucarius Pass) (pyriformis Licht.) 



Tullgren, 1909, p. 122. 

 P. canadensis. 



Pemphigus filaginis Boyer. (gnaphalii Kalt) (prociphilus gnaphalii 



Koch) (Pachypappa marsupialis Koch) (ovato-oblongus Kess- 



ler). Tullgren, 1909, p. 136. 

 P. candicans Ait Balm-of-Gilead. 



Aphis candicans Fitch. Monell, 1879, p. 26. 

 Chaitophorus candicans Thomas. Hunter, 1901, p. 87. 

 Melanoxanthus salicis Linn. Cowen, 1895, p. 117. 

 P. deltoides ]\Iarsh. (monilifera) (angulata) Cotton-wood, Necklace 



Poplar. 

 Arctaphis sp. Cooley, 1912, p. 89. "New Aphis of Cottonwoods." 

 Chaitophorus populicola Thomas. 1879, p. 104. 

 CJiaitophorus populifolia Fitch (stevensis Sanborn). Sanborn, 



1904, p. 36 and 1906, p. 225. 

 Chaitophorus populifoliae (Fitch). Hunter, 1901, p. 88. 

 M elanoxantherium salicti Harris. Weed, 1891, p. 290. 

 Pemphigus betae Doane. Gillette, 1912, (24th Rept. Exp. Sta.) 



p. 28. "On Cottonwood." 

 Pemphigus bursarius Linn? Patch, 1913, Bui. 213, p. 78. 

 Pemphigtts oestlundi Cockerell, 1906, p. 34. 

 Pemphigus populicaulis Fitch. Sanborn, 1904, p. 20. 

 Pemphigus populicaulis Fitch. Jackson, 1908, p. 193. 

 Pemphigus populiconduplifolius Cowen. Jackson, 1908, p. 217. 

 Pemphigus populitransversus Riley. Sanborn, 1904, p. 22. 

 Pemphigus populitransversus Riley. Jackson, 1908, p. 207. 

 Pemphigus pseudobyrsa Walsh. Jackson, 1908, p. 199. 

 Phylloxera popularia Pergande. Pergande, 1904b, p. 266. 



(In galls of Pemphigus transversus Riley). 

 Phylloxera prolifera Oestlund. Oestlund, 1887, p. 17. (In galls 



of Pemphigus populicaulis Fitch). 

 P. Fremonti S. Wats. 



Chaitophorus populicola Thomas. Williams, 1891, p. 9. 

 Melanoxanthus salicti (Harris). Williams, 1891, p. 9. 

 Mordwilkoja oestlundi (Cockerell) (Pemphigus vagabundus 



Walsh) Davis, 1911, p. 4. 

 Pemphigus populicaulis Fitch. Williams, 1891, p. 9. 

 Pemphigus p pulimonilis Riley. Davidson, 1910, p. 374. 

 Pemphigus populiramulorum Riley. Jackson, 1908, p. 209. 

 Pemphigus populitransversus Riley. Williams, 1891, p. 9. 

 Pemphigus pseudobyrsa (Walsh). Williams, 1891, p. 9. 

 Phylloxera prolifera Oestlund. Williams, 1891, p. 9. 

 Thomasia populifoliae (Fitch). Essig, 1912a, p. 716. 

 P. grandidentata Michx. Large-toothed Aspen. 



Aphis populifoliae Fitch. Thomas, 1879, p. 102. 



Aphis (Dactynus) populus-grandidentata Raf. Rafinesque, 1818. 



