The Aphididae of Nebraska 59 



Found on Solid ago canadensis. Ashland, September 20, 1890. 

 It works on the upper side of the leaves, along the midrib and 

 causes a downward swelling of the central portion of the leaf and 

 a corresponding upward curling of the margins, so that the lice 

 are completely surrounded. They are preyed upon by the larva 

 of a small syrphid fly, which gets within the gall and soon de- 

 stroys its occupants. Two or three individuals were found which 

 I think were males, but a dissection was necessary to determine 

 that conclusively, but I was unable to do so, owing to circum- 

 stances that made it impossible. They differed but little from 

 the females. In many of the galls eggs of a greenish yellow color 

 were found quite plentiful. The aphids were watched for some 

 time but neither pupae or winged forms could be found. The 

 general appearance of the louse is similar to S. amygdali (Fouse), 

 but it differs in honey tubes, antennae and tail and in lacking the 

 large marginal spots found in all the forms of that species. 



Cotypes in the collection of the University of Nebraska (nos. 

 91, 92) and of the U. S. National Museum (no. in). 



■J2,- Aphis symphoricarpi Thomas. 



Thomas, Bull. 111. St. Lab. Nat. Hist., 2, p. 12, 1878, and Ins. 111., 8th 

 Rep., p. 99 (1879 (in part)). 



Oestlund, Syn. Aph. Minn., p. 50 (1887). 

 Apterous viviparous female: Green; the stem-mother is generally some- 

 what brownish. Head brownish. Eyes red. Antennae about two thirds 

 as long as the body, minutely annulate ; I and II brown ; III, IV and V 

 whitish except the tips, which together with VI are black; VII pale, as 

 long as III. Legs pale, with dusky femoral and tibial tips and tarsi. 

 Honey tubes dark, shorter than the hind tarsi. Tail nearly as long as the 

 honey tubes, yellowish. The stem-mother is broadly oval in outline and 

 2.80 mm. long. 



Pupa: Pale green, smaller than the apterous females. Wing-pads pale 

 greenish. 



Winged viviparous female: Head and thorax black. Antennae not as 

 long as the body; III-V with sensoria; VII longer than III. Eyes dark 

 brown. Wings with yellow insertions, heavy straight subcostal, prominent 

 blackish oblique veins and broad stigma. Second branch of cubital arising 

 nearer the base of the first branch than to the apex of the wing. Abdo- 

 men green, with black marginal spots and more or less broken, transverse 

 bands on the dorsum. Legs black, with base of femora and sometimes a 



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