U. S. D. A., B. E. Tech. Ser. 2r., T'l. I. Issued May 4, 1912. 



PAPERS ON APHIDIDJ^:. 



STUDIES ON A NEW SPECIES OF TOXOPTERA, WITH AN ANALYTICAL 

 KEY TO THE GENUS AND NOTES ON REARING METHODS. 



By W. J. Phillips and J. J. Davis, 

 Entomological Assistants, Cereal and Forage Insect Investigations. 



INTRODUCTION. 



Toxoptera muhlenhergise has been under observation since the sum- 

 mer of 1908. On July 24 of that year Mr. V. L. Wiklermuth, of this 

 bureau, found this apliis at New Paris' Ohio, on a species of MuJilen- 

 hergia. It was thought at the time that it was Toxoptera graminum, 

 to which species it bears a very close resemblance. The senior author 

 found the same aphis at Kichmond, Ind., later in the month, ])laced 

 it in rearing on Muhlenhergia, and obtained the sexes in October. 

 From the sexes it was very evident that the species was not T. grami- 

 num, as the male is wingless. Since T. muhlenhergix bore so close a 

 resemblance to the destructive ''green bug," a species that the senior 

 author was then studying, he has also kept the former species under 

 observation since that time. The junior author has named and 

 described the sj)ecies and has also drawn up a key for the identification 

 of the members of this genus. The authors wish to thank Mr. Pliili]) 

 Luginbill, of the Bureau of Entomology, for his assistance in rearing 

 through consecutive generations of this species. 



description of the species. 

 Toxoptera muhlenbergle n. sp. 



WINGED VIVIPAROUS FEMALE. 



(Fig. 1.) 



Head brownish, thoracic plate dark brown, and abdomen pale 

 green. Usually a small pale-yollowish area on the abdomen around 

 each cornicle. Eyes black and ocelli dusky. Antcniuv blackish 

 excepting segments I, II, and the extreme base of III, which are 

 pale brownish; slightly imbricate, 3 to 7 circular sensoria in a row 

 on segment III, the usual one near the distal end of ^', and several 



1 



