58 KANSAS UNIVERSITY SCIENCE BULLETIN. 



drical and imbricated, 0.25 mm. long, or about twice the length 

 of the tarsi. Style concolorous with the abdomen, hirsute, also 

 armed with short spines. It is bluntly rounded at the distal 

 end and 0.09 mm. long, or a little less than one-half the length 

 of the honey-tubes. Total length of the body, 1.18 mm. 



This form was taken July 9, on ironweed ( Vernoniabaldwini) . 

 It is gregarious, and colonizes the tender terminal growing 

 parts. This form is similar to the genus Sipha in size, shape, 

 and especially in the construction of the third and fourth anten- 

 nal joints, inasmuch as they are not as distinctly divided as is 

 common in the genus ApJiis, but appear as a gradation between 

 the two genera. 



Aphis. Plate V, fig. 35. 



Head black. Antenmo dark, imbricated, and almost naked ; 

 length of segments : I, 0.09 mm. ; II, 0.05 mm.; Ill, 0.36 mm.; 

 IV, 0.23 mm.; V, 0.18 mm. ; VI, 0.09 mm. ; VII, 0.34 mm. ; 

 total length, 1.30 mm., or extending to near the center of the 

 abdomen. Sensoria circular, fifteen to twenty on the third 

 joint, ten to twelve on the fourth, usually two or three on the 

 fifth, and a cluster of four or five at the distal end of the sixth. 

 Eyes black ; ocular tubercles prominent, tinged with red ; ocelli 

 normal. Beak dark, 0.54 mm. long, extending midway between 

 the pro- and mesocox?e. 



Prothorax black, lateral tubercles prominent. Thorax black ; 

 wings hyaline, veins brown. Stigma light brown, 0.18 mm. 

 broad and 1.07 mm. long. Total wing expansion, 7.70 mm. 

 Legs hirsute, dark except the tibia, which are a shade lighter. 



Abdomen blackish. Honey-tubes black, clavate, being di- 

 lated at the distal ends ; length, 0.18 mm., being two and one- 

 half times the length of the tarsi. Style black, hirsute, bluntly 

 rounded at the tip and turned dorsad; 0.09 mm. in length, or 

 one-half the length of the honey-tubes. Total length of the 

 body, 1.90 mm. 



This form was taken April 25, on waahoo {Eaonymas atro- 

 parp'ireus) . It is gregarious in habit, and colonizes the leaves. 



Aphis maidis Fitch. Plate XI, fig. 66. 



Head black. Antenna^ black, with few scattered hairs ; 

 length of segments: I, 0.07 mm. ; II, 0.07 mm.; Ill, 0.34 

 mm. ; IV, 0.19 mm. ; V, 0.16 mm. ; VI, 0.10 mm. ; VII, 0.14 



