104 



PAPERS ON CEREAL AND FORAGE INSECTS. 



from tropical America; and Chenopodium album, Capsella bursa- 

 pastoris, Brassica oleracea, and B. nigra, Polygonum' persicaria, 



Rumex 



crispus. 



and Anthemis co- 



tula, which are adventitious from 

 Europe or have been naturalized 

 from Europe. They are all annuals 

 except a few which are sometimes 

 biennials. 



During March and April, 1910, in 

 the vicinity of San Benito, Tex., the 

 writer found this species infesting 

 the roots of the following unculti- 

 vated plants: Vervain {Verbena 

 canadensis) , common nightshade 

 {Solarium nigrum), skullcap (Scu- 

 tellaria drummondii) , Teiwrium 

 laciniatum, amaranth (Amaran- 



Fig. 56. — The corn root-aphis 

 rous female and hind tibia. 

 Forbes.) 



Ovipa- 

 (From 



thus 



and at 

 of Iva 



sp.), Selenia (?) sp. 7 

 Brownsville on the roots 

 xanthifolia ( ? ) . 



Kothmgr was found to indicate that it had attacked either corn or 

 cotton, although further investigations will be required to either 

 prove or disprove its occurrence on fj 



these or other cultivated plants. /' 



INJURY TO CORN. 



Aphis maidi-radicis has been par- 

 ticularly injurious to corn in Mary- 

 land, Ohio, Indiana, and Illinois, and 

 has done serious injury to this crop 

 in eastern Pennsylvania, New Jersey, 

 the Virginias, and the Carolinas. In 

 badly infested fields the crop is some- 

 times almost entirely lost, as shown in 

 the accompanying illustration (Plate 

 V, fig. 1), from a photograph by Mr. 

 W. J. Phillips, of a field in Indiana. 



In Illinois its seasonal history, ac- 

 cording to Mr. J. J. Davis, is, in brief, 

 as follows: The eggs may be found 

 hatching in the field from April 8 to 

 May 22, and from ten to twenty-two generations may follow. S 

 forms (figs. 56-58) are produced in the latter part of September 



Fig. 57. — The corn root-aphis 

 less male and antenna. 

 Forbes.) 



Wing- 

 (From 



exual 

 or in 



°Loc. cit. 



