The Aphididae of Nebraska 1 3 



9. Pemphigus rhois Fitch. 



On Rhus glabra, West Point, July 29, 1890, specimen no. 9, 



University of Nebraska collection. 



10. Pemphigus tesselata (Fitch). 



Fitch, 4th Rep. St. Cab. Nat. Hist. (1851). Eriosoma tesselata. 



Glover, U. S. Ag. Rep., p. 39 (1876). 



Glover, Unpub. PI. Horn., Ill, fig. 10, imbricata. 



Thomas, Ins. 111., 8th Rep., p. 139 (1879). Schizoneura tesselata. 



Osborn, Can. Ent., XIV, p. 61 (1882). Pemphigus tesselata. 

 Apterous viviparous female: General color bluish black. Antennae 

 5-jointed, III longest, blackish brown, with whitish ring at the articula- 

 tions, with a few very fine hairs, 0.80 mm. long. Head brownish, a broad 

 blackish brown band extending along each side just at the base of the 

 antennae and the eyes, which turns in at right angles and runs transversely 

 across the base of the head, where it is divided by a narrow whitish line 

 on each side of which is a small circular dot ; pulverulent but not floccu- 

 lent. Eyes small, black. Beak reaching to hind coxae. Legs short. Ab- 

 domen with segments distinctly separated, and with longitudinal striae 

 forming square checker-like places on the dorsum. In each of these 

 squares is a circular, pore-like spot from which proceed long shreds of 

 flocculent matter, which cover the abdomen and extend out beyond the 

 tip. Apex of abdomen hairy. Length of body 4 mm. 



On the under side of the leaves of ash (Fraxiuus amcricanus), 

 causing the leaves to curl and become distorted. Ashland, May 

 15, 1890. 



I was obliged to leave the vicinity before the winged form ap- 

 peared, so did not procure any of them. The following descrip- 

 tion is taken from Professor Osborn's paper on this species in 

 Can. Ent., XIV, p. 62: "Fresh specimens of winged females 

 cleaned in alcohol are described in Ms. by Dr. Hagen as ■ Head 

 and antennae black, prothorax pale dirty whitish ; thorax chest- 

 nut brown ; abdomen pale whitish gray, above with six rows of 

 blackish spots ; beneath with four blackish fine lines near the 

 middle, not reaching the tip ; legs brown, tibiae and tarsi paler ; 

 wings opaque, veins pale, except the mediana of the fore wings, 

 which is brown. Full grown nympha is similar to the imago ; 

 the wing coverings are black.' 



" ' Alcoholic specimens of winged viviparous female were dark 

 bluish black with the white filaments on the abdomen less promi- 



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