BIOLOGICAL STUDIES ON THREE APHIDID^. 141 



1891. Weed, C. M.— Insects and Insecticides. < Hanover. N. H., pp. 209-210. 

 fig. 110. 



The corn root-aphis (Aphis maidis ?). General life history; gives the 

 rotation of crops as the only known successful remedy. 



1891. Williams, T. A. — Host-plant list of North American Aphididre. < Special 



Bui. 1, Univ. Nebr. , Dept. Ent., Lincoln, pp. 10, 14, 16, 21, 23. 



Lists of food plants of Aphis maidis, feeding on roots, as dock (Rumex 

 altissimus) , Setaria glauca, 8. viriclis, knotweed (Polygonum persicaria), 

 plantain (Plantayo major), ragweed (Ambrosia trifida), and smartweed 

 (Polygonum sp. ). 



1892. Bruner, L. — Report of Entomologist. <Ann. Rep. Nebr. State Board Agr. 



for 1891, Lincoln, pp. 300-304, fig. 77. 



Aphis maidi-radicis Forbes. Gives descriptions of all forms. Quotes th(» 

 life history from that given by Professor Forbes. 



1892. Riley, C. V., and Howard, L, O. — Review of Professor Forbes's Sixth 

 Report. < Insect Life, U. S. Dept. Agr., Washington, D. C, Vol. IV, 

 Nos. 9 and 10, p. 293. 



Mentions that it contains a summary history of the corn root-aphis and a 

 colored plate of same. 



1892. Webster, F. M. — Early published references to some of our injurious 

 insects. < Insect Life, V. S. Dept. Agr., Washington, D. C, Vol. IV, 

 Nos. 7 and 8, p. 264. 



Gives references to the original descriptions of Aphis maidis, root and 

 aerial forms. Gives reference to a note in American Farmer, Vol. IV, p. 71. 

 May 24, 1822, from Mr. Tho. Emory, of Poplar Grove (State not given), 

 relating to a disease of wheat known as " sedging," who says, " I believe this 

 insect is the same as that known by the name of the root-louse in corn, so 

 frequently found in that plant," etc. 



1892. Riley, C. V., and Howard, L. O. — The corn root-aphis. < Insect Life, 



U. S. Dept. Agr., Washington, D. C, Vol. IV, Nos. 7 and 8, p. 285. 



Short review of Doctor Weed's article on the corn root-aphis, published as 

 a bulletin of the Illinois State Laboratory of Natural History. 



1893. Riley, C. V., and Howard, L. O. — The corn-root plant-louse. < Insect 



Life, U. S. Dept. Agr., Washington, D. C, Vol. VI, p. 32. 



Crop of corn in Maryland owned by E. P. Thomas was damaged 50 per 

 cent last year by this aphis; also injury this year (June 27, 1893). 



1894. Forbes, S. A.— Eighteenth Report of the State Entomologist of Illinois. 



<Trans. Dept. Agr. 111. for 1893, Springfield, Vol. XXXI, pp. 57, 58-85, 

 PI. VII, figs. 5, 6, PI. VIII, figs. 1, 2, 3, 4, 5. Separate: Springfield, 111., 

 1894. 



The corn root-aphis (Aphis maidi-radicis Forbes). In.iury to corn and to 

 other plants ; life history ; relation to the corn leaf-aphis ; natural enemies ; 

 economic procedure; discusses in full (!) rotation, (2) fertilizers and insecti- 

 cides, (3) breaking up the ants' nests in fall by plowing, etc., (4) early 

 spring plowing, etc. Descriptions of wingless, winged, and pupa of vivip- 

 arous female, wingless oviparous female, wingless male, and egg. 



1894. OsBORN, H. — Corn insects: Their injuries and how to treat them. <Io\va 

 Agr. Exp. Sta., Des Moines, Iowa, Bui. 24, pp. 994-995, fig. 1. 



Mentions Aphis maidi-radicis as an important corn insect, although as yet 

 it hardly seems probable that the species has become very much distributed in 

 Iowa. 



