SANBORN : KANSAS APHIDID.E. 25 



Genus Schizoneura Hartig. 



Aiitennte six-jointed ; the third joint the longest, fourth and 

 fifth about equal in length. When annulated the sensoria are 

 transverse, and when smooth the sensoria are circular. Beak 

 moderately long in the adult, sometimes extending to the meta- 

 coxic ; in the young it sometimes extends to the end of the ab- 

 domen. Wings moderately long ; the first two discoidals of the 

 cephalic wing arise close together ; the cubital is obsolete at the 

 base and once branched. Subcostal vein of the caudal wings 

 nearly straight, with two discoidals. Legs short. The body, 

 with but few exceptions, is covered with a pulverulent or cot- 

 tony secretion. Honey-tubes rudimentary or absent. Style 

 obsolete or rudimentary. 



Schizoneura americana Riley. Plate VI, fig. 37. 



Head black. Antennae dark, bare, and annulated with sen- 

 soria ; length of joints : I, 0.05 mm. ; II, 0.05 mm. ; III, 0.37 

 mm. ; IV, 0.09 mm. ; V, 0.10 mm. ; VI, 0.09 mm., including 

 the unguis; latter alone, 0.01 mm.; total length of antennae, 

 0.75 mm., extending to the insertion of the caudal wings. Sen- 

 soria transverse, about twenty-two on the third, four to six on 

 the fourth, four to six on the fifth, about three on the sixth ; also 

 three or four small circular ones at the distal end of the sixth 

 or base of the unguis. The distal end of the latter is armed 

 with four or five short capitate hairs. Eyes black ; ocular tuber- 

 cles present but not prominent ; ocelli present and conspicuous. 

 Beak dark, 0.81 mm. long, extending to the mesocoxa\ 



Prothorax short and dark ; wings hyaline, venation medium 

 in width, each bordered with a very faint smoky tinge on each 

 side about twice as wide as the vein itself. Stigma dark, 0.19 

 mm. broad and 0.63 mm. long. Total wing expansion, 5.80 mm. 

 Legs black, slightly hirsute, and normal. 



Abdomen reddish brown ; honey-tubes present but not con- 

 spicuous, being almost obsolete. Style obsolete. Total length 

 of the body, 2,44 mm. 



This form was taken June 16, on the elm ( Ulmus americmia.) 

 They colorize the ventral side of the leaves, causing them to 

 curl. When numerous they give the leaves a whitish appear- 

 ance and cause the terminal ones to bunch together, which gives 

 the lice more protection. When the leaves begin to turn yellow 



