The Aphididae of Nebraska y\ 



Legs as in apterous form or sometimes with base of femora and part of 

 tibiae yellowish. Wings with yellowish insertions and subcostal ; stigma 

 conspicuous, brown; oblique veins heavy and blackish. Honey tubes and 

 tail as in the apterous female. Length of body 2.50 mm., to tip of wings 

 4.10 mm. 



One of our commonest aphids. Found on Potamogcton, Sagit- 

 taria, Ammonia, Bidens, Alisma, /uncus, Naias, Typha, Nehtmbo, 

 Kymphaca, Lew.ua and many other plants growing along the 

 water's edge; generally most plentiful from July to September. 

 Ashland, Lincoln, Weeping Water, Fremont. One of the most 

 variable species with which I am acquainted, both with respect 

 to size and coloration. 



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

 120-124) and of the U. S. National Museum (nos. 30, 31, 32). 



89. Rhopalosiphum rhois Monell. 



Monell, Bull. U. S. Geol. Sur. Ter., V, 1, p. 27 (1879). 

 Oestlund, Syn. Aph. Minn., p. 75 (1887). 



Apterous viviparous female: General color reddish brown (in some indi- 

 viduals this becomes more or less of a dark green). Antennae black, with 

 paler base. Eyes black. Beak short. Honey tubes 3-4 times the tarsi, 

 dusky to blackish, clavate. Tail slender, same color as abdomen. Legs 

 yellowish brown, with dusky tarsi. 



Pupa: Lighter colored, often quite green. Wing-pads pale greenish. 

 Tail very short and conical. Size smaller than the apterous female. 



Winged viviparous female: Head and thoracic lobes black; rest of body 

 varying from brown to olive green. Antennae black, a little longer than 

 the body, on inconspicuous frontal tubercles; III and VII subequal in 

 length, either longer than V and VI together. Wings slender, with black- 

 ish oblique veins. Legs, honey tubes and tail much as in the apterous 

 female. The honey tubes rather longer and more clavate. Tail about 

 one third the honey tubes in length. Length of body about 1.90 mm., to 

 tip of wings 3.80 mm. 



On under side of leaves of sumach (Rhus glabra). Lincoln, 

 September, 1888; West Point, July, 1890. It varies considerably 

 in coloration ; is generally found in large companies along the 

 midrib of the leaves. 



Specimens in the collection of the University of Nebraska (no. 

 125) and of the U. S. National Museum (no. 24). 



155 



