76 Wisconsin Academy of Sciences, Arts, and Letters. 
flavusy Lachnus Mordwilko, 1895. Rab. Lab. Zool. Kab. Varcb. 
Univ., p. 133. 
Picea aMes. 
For description in German see Zool. Anz. XVIII, 1895, p. 102. 
flavus, Sipha (Forbes), 1884. Thirteenth Kept. Nox. & Ben. In¬ 
sects, Ill., p. 42, fig. Chaitophorus. 
Arena sativa, Digitaria sanguinalis, Echinochloa crus-galU, Phleum 
pratense, Poa pratensis, Sorghum dora, S. halepense, 8. sac- 
charatum, Setaria glauea, Zea mays. 
flocculosa, Lachnus Williams, 1911. Aphididae of Nebraska, p. 22. 
Pinus ponderosa. 
flocculosa, Pterocomma (Weed), 1891. Insect Life, III, p. 291, 
fig. Melanoxanthus. 
Salix cinerea. 
floccus, Chernies Patch, 1909. Psyche, XVI, p. 137. 
Picea marina, P. ruhra, Pinus strohus. 
florentina, Phylloxera Targioni-Tozzeti, 1875. Bui. Soc. Ent. Ital., 
VII, p. 287. 
Quercus farnetto, Q. ilex, Q. sessilifolia. 
floris-rapae, Aphis Curtiss, 1842. Jour. Royal Agr. Soc., Ill, p. 55. 
Brassica oleracea. 
foae, Phylloxera Borner, 1909. Zool. Anz., XXXIV, p. 26. 
Quercus rohur. 
fodiens, Schizoneiira Buckton, 1881. Mon. Brit. Aphides, III, p. 
94, fig. 
Bromus arienariusf, Rihes nigrum. 
foenlculi, Siphocoryne Passerini, 1860. Gli Afidi, p. 37. 
Conium maculatum, Daucus carota, Foeniculus vulgare, Pastinaca 
sativa. 
foUicularius, Pemphigus Passerini, 1861. Atti Soc. Ital. Sci. Nat. 
Ill, p. 400. 
Pistacia terehinthls. 
folsomii, Aphis Davis, 1908. Ent. News, XIX, p. 143, fig. 
P seder a quinquefolia. 
