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minating seeds were then transferred to sterile soil in test tubes 

 and pots. Mycelia from the cultures were introduced. In- 

 fection occurred in the greatest number of cases. In some pots 

 every seedling was infected and produced spore pustules. Con- 

 trols uninfected. 



The mycelial cells from the beginning of germination are 

 uni-nucleated (the saprophytic mycelial cells). The mycelial 

 cells when broken apart are uni-nucleate and germinate as above 

 described, producing a uni-nucleated mycelium. No fusion of 

 any of the hyphal cells of the saprophytic mycelium occurs. 



The parasitic mycelium in the host plant is intercellular, 

 growing and spreading rapidly. Certain of the vegetative 

 hyphae are uni-nucleate but as one follows the hyphae toward 

 the sorus, bi-nucleate cells are found to predominate. Large- 

 sized hyphae were observed to penetrate through several cells 

 of the host. These are supposed to be special nutritive hyphae. 

 Haustoria are rare. Those observed had penetrated the cell 

 walls of the host plant and were clavate in form. 



By continued branching and growth of the intercellular my- 

 celia, the cells of the host plant are pushed apart or broken down. 

 This is the beginning of the formation of the sorus. At this 

 stage of development the mycelium of the fungus stains densely. 

 All the mycelial cells of the young sorus are bi-nucleate. The 

 first appearance of spore formation occurs among these hyphae 

 rich in protoplasm. The spore begins by very rapid enlarge- 

 ment of one of the bi-nucleate cells. This growth is so rapid 

 that the enlarging cell encroaches upon the neighboring hyphal 

 cells from which it apparently now draws a portion of its sus- 

 tenance. The surrounding cells are brought completely under 

 the dominance of the young developing spore. As the spore 

 cell enlarges, the functioning nurse cells adhere or fuse to its 

 wall and become the sterile cells (pseudospores) about the fertile 

 spore, the whole forming the spore-ball. At the beginning, the 

 young spore contains two nuclei, which soon fuse. Thus the 

 mature spore becomes uni-nucleated. By the rapid enlarge- 

 ment of the spore-balls, the sorus bursts the surrounding host 

 tissue, which frees the spores. 



The second paper was by Mr. S. A. Wingard on "A Yeast 

 Disease of the Lima Bean." The following abstract was fur- 

 nished by the speaker: 



