REPORT OF THE STATE ENTOMOLOGIST I909 79 



amount of honeydew excreted. The latter occasionally collects 

 in rather thick, viscid masses on the foliage, and not infrequent- 

 ly is so abundant as to keep the sidewalk beneath infested trees 

 wet even in hot summer weather. This insect was excessively 

 numerous in many sections of the State in 1909, seriously injur- 

 ing the foliage of many beautiful trees and in not a few in- 

 stances causing 10 to 2^i of the leaves to drop. In very severe at- 

 tacks practically all of the leaves may be seriously affected and a 

 considerable proportion drop before others have an opportunity to 

 develop. This species is usually controlled in midsummer by natural 

 enemies, the beneficial ladybeetles or ladybugs being among the 

 most active. 



Painted maple aphis (Drepanaphis acerifolii 

 Thos.). This beautiful little plant louse was very abundant and 

 rather injurious to soft maples in particular, though it occurs in 

 small numbers on the hard or sugar maple. It is easily recog- 

 nized as a small, red eyed, black and white marked plant louse 

 with prettily marked brown wings. The young are pale yellowish 

 and wingless. 



Box elder aphis (Chaitophorus negundinis 

 Thom.). This gregarious species has been somewhat abundant 

 the last few years on the relatively few box elders observed in 

 the vicinity of Albany, N. Y. It is a greenish form, the abdo- 

 men being pale green, the head browm, the latter and the pro- 

 thorax both hairy. 



Elm leaf aphis (Callipterus ulmifolii Mon.). This 

 very slight, inconspicuous, pale greenish plant louse was ex- 

 cessively abundant on the underside of American elm leaves, 

 causing serious injuries, especially in the western and southern 

 portions of the State. It was so numerous at Dunkirk and Ful- 

 ton as to cause considerable annoyance on account of the large 

 amount of honeydew dropping from the trees. 



Woolly elm aphis (Schizoneura ulmi Linn.). The 

 woolly elm aphis is easily recognized in June by the badly 

 curled leaves of white elm, usually accompanied by the dropping 

 of wax-powdered pellets of honeydew. This species is some- 

 times excessively abundant on elm foliage, the affected leaves 

 curling so as to form a cavity which may be brimful of strug- 

 gling plant lice and particles of wliitish honeydew. Professor 

 Gillette is inclined to believe that the woolly aphid, occurring 

 on the bark of elm and known as S c h i z o n u r a r i 1 y i 

 Thos., is identical with this form. 



