Williams' "The Aphididac of Nebraska" 25 



Winged viviparous female: Antennal segments III and VI filament sub- 

 equal in length, IV three fourths the length of III, V about three fourths 

 or more the length of IV, VI base, about one fourth of VI filament; seg- 

 ment III with 22 to 27 irregularly placed, circular sensoria, IV with 10 to 

 12 more or less in a row, and the usual distal sensoria on V and VI base. 

 Ml (first branch of the third discoidal) beginning at a distance nearer 

 the apex of the wing than from where Mz+t branches. Body robust. 

 Cornicles not reaching beyond the tip of the abdomen, exclusive of the 

 style. 



Wingless viviparous female: A few sensoria are borne on the basal por- 

 tion of antennal segment III, as in case of the oviparous female. No sen- 

 soria on hind tibiae. 



Winged male ? : Antennal segment III bearing 65 to 85 small, irregularly 

 placed, circular sensoria, IV with 35 to 45, and V with 25 to 30. Wing 

 venation as in the winged viviparous female. These and the character- 

 istics given in Williams' original description agree with the males (?) re^ 

 ceived from Dr. Patch. 



Wingless oviparous female: Several sensoria on the basal portion of 

 antennal segment III ; also numerous sensoria on the basal two thirds of 

 the hind tibia. Comparative lengths of antennal segments as in the other 

 forms. 



Camera liicida drawings of the head, antenna, of winged 

 viviparous female will be found on Plate VIII, fig. 122; head,, 

 antenna, cornicle, and style of the wingless viviparous female on: 

 Plate VIII, figs. 123 to 125; antenna of winged male as fig. 126; 

 and antenna of wingless oviparous female as fig. 127. 



86. Myzus persicae Sulz. (RJwpahsiphum dianthi Schrank). 



87. Rhopalosiphum poae Gillette (Rhop. dianthi \ar. poae Williams). 



" Rhopalosiphum dianthi (Schr.) var. poae n. var. No. 119. 

 On Blue grass, Greenhouse, Lincoln, Feb. i, 1890." 



On this slide are two winged^ one pupa, and several immature. 

 Williams' variety poae is a synonym of Gillette's Rhopalosiphum 

 poae, originally described in the Canadian Entomologist, 40: 61, 

 Feb., 1908. 



88. Rhop. nymphaeae (Linnaeus). 



89. Rhop. rhois Monell. 



90. Amphorophora ampulata Buckton ? 



No specimens of what Williams questionably considered this 

 species are in the Nebraska Collection. 



277 



