342 Agricultural Experiment Station, Ithaca, N. Y. 



in the moist chamber has been made with caution, a few pure cul- 

 tures are quite likely to result. 



Bacteria will be shut out by the acid in the medium, and if the 

 culture is free from other fungi in a few days the mycelium will be 

 visible as a silky white growth which spreads over the surface of 

 the bean stems, growing downward over them and also outward 

 onto the surface of the glass tube. This growth continues to 

 advance for several days with quite an even advance edge to the 

 weft. In the course of four or five days, or one week, from the 

 time that the mycelium is visible to the eye in the culture tube, 

 there will appear first on the stems at certain points, and later on 

 the surface of the glass tube, minute white powdery looking tufts 

 on the mycelium. These are made up of closely and profusely 

 branched threads, the branching sometimes presenting numerous 

 and quite regular dichotomies, at other times quite irregular, and 

 the terminal branches profusely lobed, the lobes standing in all 

 directions and considerably more slender than the threads of the 

 mycelium, and from 10// to 20/y or more in length, occupying the 

 distal portion of the branch for a distance from 20// to 50//, 

 Another form of branching will also be present in which the closely 

 set branches diverge at quite strong angles and are quite regularly 

 constricted, presenting a moniliform appearance, and become 

 eventually divided into short cells. These branches become more 

 closely compacted and interwoven, forming rotund bodies at first 

 white and quite small, but eventually 2 to 4 millimeters in diameter 

 and of a brown color. These bodies are probably sclerotia. 



Upon the surface of these sclerotia are diverging threads with 

 numerous moniliform cells which resemble chains of conidia. 

 These are not true conidia, since they do not easily become sepa- 

 rated. By breaking down the sclerotia, or by scraping the surface, 

 many of them become separated into chains of two or three cells or 

 even become entirely sejDarate. If placed in water, or in suitable 

 medium, they will germinate, thus functioning like conidia. 



The sclerotia have been kept for several months, but in no case 

 has any other stage of the fungus been developed from them. 



At present it can not be correlated with any known group of 

 fungi, but there are reasons for supposing that the sclerotia may be 

 the resting stage of some hymenomycetous fungus. Frequently the 

 threads become united into rope like strands and cliange to a brown 

 color. 



