BIOLOGIC FORMS 11 



inch clay pots. Only ten plants were left in each pot and the first leaf 

 of each was inoculated when six or seven days old. The plants were 

 trimmed whenever necessary so as to leave only the one inoculated leaf 

 on each plant. Fresh, viable uredospores were used for inoculations 

 except where otherwise specified. The spores were put on the leaves 

 with a flat inoculating needle which had been previously moistened 

 in order that the spores might better adhere to the leaf surface. The 

 pots were then placed in shallow pans filled with water, or on wet 

 sand, and covered with bell jars for forty-eight hours. In nearly all 

 cases a fine film of moisture covered the leaves during a considerable 

 part of the time that they were under the jars. This, together with a 

 moderate temperature, made the conditions for infection ideal. After 

 the removal of the bell jars the plants were kept on greenhouse benches 

 in such locations as to reduce to the minimum the danger of accidental 

 infection. 



The grains used were the following, the numbers, except where 

 specified, being Grain Investigation numbers of the United States 

 Department of Agriculture : 



Fife wheat, Minnesota No. 163 



Velvet Blue Stem wheat, Minnesota No. 169 



Minnesota No. 188 wheat, a cross between White Fife and Ladoga 

 Fife 



Manchuria barley, Minnesota No. 105 



Early Gothland oats, Minnesota No. 295 



Swedish rye, Minnesota No. 2 



Kubanka 1516 Nos. 8 and 9 pedigreed Dickinson, N. Dak., 1910 



Kubanka 2094 



Arnautka 288 



Arnautka 1431 



lumillo 1736 (1736-II-3 selected at Amarillo, Tex., 1910) 



Einkorn (Triticum monococcum) 2433 Nos. 4, 6, 7, and 8 pedi- 

 greedDickinson, N. Dak., 1910 



Emmer (Triticum dicoccum) 1522 



Khapli (an Indian Emmer) 



Of these the Kubankas, Arnautka, and lumillo are varieties of 

 Triticum durum. The durums generally have the reputation of being 

 more resistant to rusts than are the ordinary wheats (Carleton 1905, p. 

 9). Einkorn, also, is quite resistant while the emmers vary greatly, 

 one used in this work, G. I. No. 1522, not being very resistant. Khapli 

 is an emmer obtained from India by E. C. Johnson, formerly Cereal 

 Pathologist in the office of Grain Investigations, United States Depart- 

 ment of Agriculture. It has no Grain Investigation number. It is the 

 most resistant of all the forms used. 



