Elm leaf curl and woolly Elm leaf curl and woolly apple aphid elmleafcurlwooll203patc Year: 1912 242 MAIXE AGR[CULTL-R.\I, EXPERIMK-VT STATION'. I912. leaf migrants at the base of water shoots of an uninfested mountain ash on the Campus. As the migrants are much more docile about sundown than earlier in the day this was done about 7 P. The}- moved but little, most of them creeping to the ventral side of a leaf and remaining there: and during the night producing nymphs which sought the leaf axils of the water shoots so that by the afternoon of June 22, the tinv nymphs had already fed enough an
Elm leaf curl and woolly Elm leaf curl and woolly apple aphid elmleafcurlwooll203patc Year: 1912 242 MAIXE AGR[CULTL-R.\I, EXPERIMK-VT STATION'. I912. leaf migrants at the base of water shoots of an uninfested mountain ash on the Campus. As the migrants are much more docile about sundown than earlier in the day this was done about 7 P. The}- moved but little, most of them creeping to the ventral side of a leaf and remaining there: and during the night producing nymphs which sought the leaf axils of the water shoots so that by the afternoon of June 22, the tinv nymphs had already fed enough and secreted enough white wax to give the typical 'woolly' appearance to the young colonies. These and the progeny thrived on the mountain ash in a perfectly normal way. culous spots. Antenna 5-jointed, joint 3 more than equaling 4 and 5 together in length. Causing and inhabiting elm leaf curl. Second generation. Apterous vk'iparous forms which do not become so large as the stem mother. The antenna is normally 6-jointed (Fig. 461). Inhabiting leaf curl and giving birth to migrants. Third generation. \\'inged viviparous female: Body dusky, the abdomen slightly reddish: legs either dusky or yellowish red. Antennae as long as head and thorax together, dusky, rarely yellowish, not pilose, but with a few short setous points; 6-jointecl. The annulation of the joints in diflferent collections and from different localities varies greatly. Figs 451. 452. 454. Sequence of Gener-^tioxs. Descriptive. Egg mm. long, gamboge- yellow, inclining to brown in color, with no especial external sculpture. In crevices under elm bark. Fig. 443. Stem mother. (From Riley.) Stein mother: Pale yellowish- red, with black members when first hatched; the red deepening and becoming purplish or livid with age. When mature, aver- aging mm. in length, globose or pyriform, with subobsolete honey-tubes and six dorsal rows of darker piliferous and tuber-
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