86 THE BUSTS OF GRAINS IN THE UNITED STATES. 



Page. 

 Preventive measures against rusts. See Rusts, grain, prevention. 



Prillieux, Ed., on legislation to restrict the growing of barberries 29, 82 



Pritchard, F. J., and Bolley, H. L., on investigations of rust 52, 80 



Puccinia corona ta. See Oats, leaf rust. 



coronifera, occurrence on oats 13, 45 



cryptandri, viability of uredospores 55 



dispersa, occurrence 14, 46, 55, 59 



relation to leaf rust of rye as known in America 14 



glumarum, yellow rust of wheat, occurrence 8, 46, 71 



graminis. See Rusts, grain. 



a venae. See Oats, stem rust, 

 hordei. See Barley, stem rust, 

 secalis. See Rye, stem rust. 

 tritici. See Wheat, stem rust. 

 phlei-pratensis. See Rust, timothy. 



poarum, wintering of uredo 49 



poculiformis, synonym for Puccinia graminis 28 



rubigo-vera. See Rye, leaf rust; and Wheat, leaf rust, 

 secalis. See Rye, leaf rust, 

 tritici. See Wheat, leaf rust, 

 simplex. See Barley, leaf rust. 



straminis, wintering of uredo 46 



vexans, adaptation to unfavorable conditions 47 



Quack-grass, host plant for grain rust 49 



Rainfall. See Precipitation. 



Reproduction, sexual, in the grain rusts 33 



Resistance of plants to rust. See Rusts, grain, resistance. 



Rhamnus spp., host plants for grain rust 13, 14, 32, 74 



Rhode Island, legislation to restrict the growing of barberries 29 



Rostrup, E., on the investigation of rusts 15, 32, 82 



Rubus fruticosus, occurrence of rust showing origin of the binucleated condition 



in the secidium 33 



Rust, timothy, relation to grain rusts 28, 46 



Rusts, grain, secidial stage '. . . 13, 28-45, 56, 74, 76 



biologic forms, experiments to determine relationships 14-28, 75-76 



botanical characteristics 12-28, 74-76 



dissemination of the spores 53-55, 76 



distribution in the United States 8-12, 73-74 



epidemics 7-8, 10, 58-66, 74, 76-77 



first appearance in the spring 56-58 



hetercecism 28, 31, 45, 76 



kinds in the United States 8, 73 



life histories 12-28, 74-76 



physiological specializations 12-28, 74-76, 77 



prevention 66-73, 77-78 



relation of American to European forms 12-14, 32, 74, 76 



resistance in plants 15, 70-71, 77-78 



uredospores, morphological effect of change of host 25-27, 75 



viability of the spores 33-45, 52, 55, 57, 76 



wintering of the uredo generation 45-53, 54, 57, 58, 76 



Rye, leaf rust, occurrence. . . 8, 12, 14, 15, 24, 27, 28, 32, 34, 41^2, 46, 48, 49, 55, 59, 73-76 



spring, use in inoculation experiments 17 



stem rust, occurrence 11-12, 13, 15, 16, 21-22, 27-28, 34, 38, 74, 75 



216 



