42 THE SPRING GRAIN-APHIS OR GREEN BUG. 



of Kansas, also found the Hordeum pusiUum much infested later in 

 the season. In July there was an outbreak of Toxoptera on blue- 

 grass (Poa pratensis) on the grounds of the United States Department 

 of Agriculture, Washington, D. C. Later in the season the junior 

 author found it on bluegrass in the fields about Richmond, Ind. 

 In the fall of the same year (1907) this was the only plant on which 

 the sexes and eggs could be found. In fact, for Indiana, Illinois, 

 Ohio, and more northern localities bluegrass appears to be the normal 

 host, and the " green bug" is readily found upon it at any time in 

 the year even when it can be found only sparingly upon any other 

 plant. 



A number of new host plants were added to the list in 1908. Mr. 

 Kelly, of this Bureau, found Toxoptera feeding freely in the fields 

 upon Hordeum jubaturn and DisticMis spicata in Montana and upon a 

 species of Andropogon in Colorado. Mr. Ainslie found it breeding 

 freely in the fields upon Hordeum jubaturn, H. csespitosum, H. nodosum, 

 Elymus striatus, Agropyron tenerum, Bromus unioloides, B. porteri, 

 Stipa viridula, and Polypogon monspeliensis about Artesia, N. Mex. 

 In one instance Mr. Ainslie found several alfalfa plants (Medicago 

 sativa) with colonies of Toxoptera upon them, as many as 21 speci- 

 mens being observed on a single leaf. This seems very unusual and 

 we have no other records of its occurrence on this plant. Prof. C. P. 

 Gillette, of Fort Collins, Colo., found it infesting Agropyron occidentale, 

 and in 1907 he found it feeding upon bluegrass. During the summer 

 of 1908 Toxoptera was found by the junior author to breed freely 

 upon Dactylis glomerata, Eleusine indica, Eragrostis pilosa, E. megas- 

 tacliya, Sporobolus neglectus, Agropyron repens, Elymus virginicus, 

 E. canadensis, and Bromus secalinus, in his rearing cages at Rich- 

 mond, Ind. 



In 1909 and 1910 a few more plants were added to the list. Mr. 

 Ainslie found it breeding freely upon Hordeum murinum in Arizona and 

 upon Agropyron occidentale in New Mexico. Mr. Kelly found it 

 breeding freely upon millet (Chsetocloa italica) and upon Japanese 

 millet (Echinochloa crus-gaUi) in Kansas. Mr. Harper Dean, jr., then 

 of this bureau, found it feeding upon Stipa leucotricha in Texas. Mr. 

 T. D. Urbahns, of this bureau, found that it bred readily in his cages 

 at Dallas, Tex., upon Bermuda grass (Capriola dactylon), Ohsetochloa 

 viridis, Johnson grass (Sorghum halepense), and upon rice (Oryza 

 sativa). 



During the summer of 1909 Mr. T. H. Parks, of this bureau, and 

 the junior author observed that Toxoptera bred freely upon Elymus 

 striatus, Juncus tenuis, Poa compressa, Bromus commutatus, B. tec- 

 torum (?), B. inermis, sheep's fescue (Festuca ovina), hard fescue 

 (F. duriuscula), meadow fescue (F. elatior), various-leaved fescue 



