324 Wisconsin Academy of Sciences, Arts, and Letters. 
Salix amygdaloides^S. nigra. 
Aphis rumicis Linnaeus. 
Aphis salicicola Thomas. 
Arctaphis populi Linnaeus. 
Chaitophorus leucomelas Koch. 
Siphocoryne capreae Fabricius. 
Salix aurita. 
Aphis saliceti Kaltenbach. 
Siphocoryne pastinaceae Linnaeus. 
Salix babylonica. 
Aphis rumicis Linnaeus. 
Aphis saliceti Kaltenbach. 
Arctaphis populi Linnaeus. 
Chaitophorus viminalis Monell. 
Chaitophorus vitellinae Schrank. 
Siphocoryne capreae Fabricius. 
Siphocoryne pastinaeeae Linnaeus. 
Siphocoryne salicis Monell. 
Salix caprea. 
Aphis alterna Walker. 
Aphis rumicis Linnaeus. 
Aphis saliceti Kaltenbach. 
Aphis secunda Walker. 
Aphis truncata Hausmann. 
Chaitophorus capreae Koch. 
Chaitophorus salicivora Walker. 
Chaitophorus salicti Schrank. 
Lachnus viminalis Boyer. 
Pterocomma populea Kaltenbach. 
Pterocomma salicis Linnaeus. 
Siphocoryne capreae Fabricius. 
Salix cinerea. 
Aphis saliceti Kaltenbach. 
Chaitophorus salicivora Walker. 
Chaitophorus salicti Schrank. 
Lachnus viminalis Boyer. 
Pterocomma flocculosus Weed. 
Pterocomma pilosa Buckton. 
Pterocomma salicis Linnaeus. 
Salix cordata. 
Chaitophorus cordatae Williams. 
Chaitophorus viminalis Monell. 
