152 
Page. 
Myzus mahaleb, host of Aphelinus mali 125 
persicse, Allotria sp. a secondary parasite 128 
host of Aphelinus semijlavus 123, 125 
Megorismus sp. a secondary parasite 126 
prey of Aphidoletes sp 133-134 
ribis, host of Aphidius testaceipes 117. 125 
sp. on Hosackia glabra, host of Aphidius testaceipes 117, 125 
Nyssa sylvatica, food plant of Macrosiphum sp 116 
Oats, food plant of spring grain-aphis in America 41, 43 
Europe 41, 43 
(Ecanthus niveus, enemy of spring grain-aphis 136 
Oryza sativa. (See Rice.) 
Pachyneuron sp. hosts 127-128 
probable parasite of Aphelinus sp 1 27 
secondary parasite of spring grain-aphis 127-128 
Panicum sp. food plant of aphidid ] 23 
Parasites of spring grain-aphis, artificial introduction 142-143 
Passerculus sandwichensis savanna, enemy of spring grain-aphis 135 
Pasturing. (See Grazing.) 
Peach, food plant of aphidid 125 
Pemphigus fraxinifolii, host of Aphelinus mali 123, 125 
Pigweed. (See Chenopodium album.) 
(?), food plant of aphidid 125 
Plowing-under infested spots against spring grain-aphis 137 
Plum, food plant of aphidid 116, 125 
Poa annua, food plant of spring grain-aphis in Europe 41, 43 
compressa, food plant of spring grain-aphis in America 42, 43 
pratensis (see also Bluegrass). 
food plant of spring grain-aphis in America 42, 43 
Polypogon montspeliensis, food plant of spring grain-aphis in America. 42, 43 
Pooecetes gramineus, enemy of spring grain-aphis 135 
Quail, enemy of spring grain-aphis 135 
Rains, protracted, effects on diffusion of Aphidius testaceipes 121 
Reduviolus ferus, enemy of spring grain-aphis 136 
Rhopalosiphum pose, probable host of Aphelinus semijlavus 123 
Rice, food plant of spring grain-aphis in America 42, 43 
Europe 41, 43 
Rolling against spring-aphis 137 
Rye, food plant of spring grain-aphis in America 41, 43 
Schizoneura americana, host of Aphelinus mail 122, 125 
Pachyneuron sp. a secondary parasite 128 
lanigera, host of Aphelinus mail 122, 123, 125 
Scymnus sp., enemy of spring grain-aphis 136 
Seeding, late, against spring grain-aphis 141 
Siphocoryne avense should probably be called Aphis avense 47 
Siphonophora avenx= Macrosiphum granaria 13, 23 
sp. on Abutilon, host of Aphidius testaceipes 117 
Audibertia stochoides, host of Aphidius testaceipes 117 
Soap against spring grain-aphis 138 
whale-oil, against spring grain-aphis 138-139 
Sorghum, food plant of spring grain-aphis in America 43 
Europe 41, 43 
halepense, food plant of spring grain-aphis 42 
