158 Y'/isconsin Academy of Sciences^ Arts, and Letters, 
sisymbrii, Macrosiphum (Buckton), 1876. Mon. Brit. Aphides, I, 
p. 160, fig. Siphonopliora. 
Bisym'brium alliaria, 8. officinale. 
sisymbrii, Rhopalosiphon Del Guercio, 1913. Redia, IX, p. 163, 
fig. 
Sisymbrium arnottianum. 
skrjabiiii, AcjTthosipIion Mordwilko, 1914. Fauna of Russia (In- 
secta Hemiptera), I, Petrograd., p. 181. 
Malva neglecta. 
smaragdinum, Drepaiiosipbum Koch, 1855. Die Pflanzenlause 
Aphiden, p. 205, fig. 
Populiis nigra, P. pyramidalis. 
smilacis, Lachims Williams, 1911. Aphididae of Nebraska, p. 24. 
Smilax herbacea. 
smithiae, Pterocomma (Monell), 1879. Bui. U. S. Geol. & Geog. 
Surv. Terr. V, No. 1, p. 32. Chaitophorus. 
Salix alba, 8. smithiana. 
socia, Aphis Walker, 1848. The Zool. VI, p. 2217. 
Cynoglossum officinale. 
sodalis, Aphis Walker, 1848. The Zool. VI, p. 2218. 
Cynoglossum officinale. 
solanella, Aphis Theobald, 1914. Bui. Ent. Research, IV, p. 325, 
fig. 
Solatium sp. 
solani, Aphis Kittel, 1827. Mem. Soc. Linn. Paris, V, p. 151. 
Solanum dulcamara, 8. nigrum, 8. villosum. 
solani, Macrosiphum (Kaltenbach), 1843. Mon. der Pfianzen- 
lause, p. 15. Aphis. 
Atropa belladona, Convulus althaeoides, Cydonia vulgaris, Helio- 
tropium europaeum. Lychnis dioica, Satureja vulgaris, So¬ 
lanum jasminoides, 8. nigrum, 8. tuberosum. 
solani, Megoura Thomas, 18 79. Eighth Rept. State Ent. Ill., p. 73. 
Lycopersicum esculentum, Solanum sp. 
