Williams' "The Aphididae of Nebraska" 35 



lengths of segments: I, 0.114; IT, 0.065; HI, 0.83; IV, 0.609; V, 0.51; VI, 

 base, 0.14; VI, filament, 0.88; total length, 3.148 mm. Wing venation as 

 shown in figure no. Distal fourth of the cornicles plainly reticulated; 

 length 0.40 mm. Length of style, 0.23 mm. 



Camera lucida drawings of the head, antenna, wing, cornicle, 

 and style of the winged male and the antenna of the wingless 

 viviparous female are given on Plate VII, figs. 109 to 113. 



114. M. verbenae (Thomas) (Siph. verbenae Thomas). 



" Siphonophora verbenae Thos. No. 156. On Verbena, 

 Greenhouse, Lincoln, Jan. 12, 1891." 



One winged, three wingless adults (two viviparous and one 

 oviparous), and two immature on slide. 



Winged viviparous female: Antennae reaching a little beyond tip of 

 style; segment III with 16 circular sensoria in a row; lengths of segments 

 as follows : 



One wing has the media (third discoidal) only once branched, the other 

 wing has Mi arising midway between the point where M3+4 branches and 

 the tip of the wing. Cornicles slender, reticulated at distal end, and reach- 

 ing a little beyond the end of abdomen but not quite to tip of style. 



Wingless viviparous female: Antennae longer than body ; segment III 

 bearing 3 to 6 circular sensoria in a row on the basal third ; measurements 

 as follows : 



Cornicles slender, reticulated at tip, and reaching beyond tip of body but 

 not quite to end of style. 



Wingless oviparous female: Antennal segment III with 9 to 14 circular 

 sensoria in a row; measurements of segments are: 



Cornicles as in other forms. Basal two thirds of the hind tibia swollen 

 and bearing many small circular sensoria. 



287 



