66 



FIG. 65. Smut spores of Tilletia caries, p, the promycelium ; a bears young 

 sporidia ; in b, the sporidia have connected by conjugating tubes to form 

 zygospores ; c shows a portion of the mycelium which has developed from 

 a zygospore, and which bears a gonidium at s', filled with the black spores. 

 (After Tulasne.) 



FIG. 66. Resting spores germinating. A, of Tilletia caries; B, of Ustilago 

 receptaculorum. (Vines.) 



FIG. 67. Oats smut (Ustilago carbo). (After Smith.) 

 FIG. 68. Part of smutted ear of Corn. (After Tulasne.) 

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