59 



EXPLANATIONS OF THE ILLUSTRATIONS. 



Plate I. 

 iMg. I. A small totally smutted experimental field of summer barley, grown from sterilized seed, 

 which, as blossoms, had been inoculated with fresh smut spores. Many heads have 

 become only partially smutted. 

 l"ig. 2. A similar experimental field of summer wheat. The few healthy heads belong, however, 

 to smutted stalks. 



In the text this fig. 2, as a result of an inadvertent reversal of the pictures, has been 

 designated as fig. i. 



Plate II. 



Fig. I. Smutted experimental plants of the Sugar millet, which were inoculated as young ger- 

 minating seedlings. The pot at the left contained all kinds of nutrient salts, including 

 calcium nitrate, the one at the right, no combined nitrogen. In the latter the experimental 

 plants, after the addition of calcium nitrate solution, developed and formed blossoms, all 

 of which were smutted. 



Fig. 2. Smutted experimental plants from sterilized two-year old wheat grain which two years 

 previously were inoculated with smut spores at the time of flowering. The right hand 

 pot shows tlie development of smutted individuals in ]3ure vitreous sand containing all l;inds 

 of nutrient salts, including calcium nitrate. In the left hand pot development took 

 place at first without the addition of combined nitrogen. Later, however, a slight amount 

 of calcium nitrate was added in order to further the development up to the formation of 

 Ijlossoms. in this part also all individuals were smutted. 



