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The number of species occurring in this vicinity, so far as collections 

 up to the present show, are six of the twelve listed by Macbride. Be- 

 sides these, a seventh form was found differing quite materially from any 

 other species collected, and not corresponding -uith any description of 

 species listed by Macbride or any other author consulted. This form is 

 very common, and its distinctive characteristics are so much unlike those 

 of closely related individuals that it is doubtless a new species. 



Very hot days following heavy showers seemed to present conditions 

 best suited for the development of the fruiting stage of Stemonitis, and 

 from early in the spring until late in the fall such conditions were sure 

 to bring forth beautiful sporangium clusters in abundance. A hot morn- 

 ing following a thunder shower is particularly favorable. Examination of 

 old trees and stumps early in the morning often revealed the pearly white 

 Plasmodia pushing forth upon the surface. As far as we have observed, 

 all Plasmodia of this genus are of a pearly white. Repeated attempts to 

 bring these Plasmodia to the laboratory to fruit always resulted in their 

 distortion, partial development or decay. In no case were there normal 

 fruits produced, although conditions seemed to be favorable. 



A careful review of the particular habitat of each species revealed no 

 special place for each. We have found them almost everywhere, although 

 perhaps most frequently on the decaying trunks and stumps of the Bed 

 Maples that line the streets of the city. One stump of Red Maple has 

 produced for three successive years the most beautiful specimens of S. 

 Webberi; several fi'uitings being produced each season. Three were 

 noted this year. Usually an area six inches in diameter on the side of the 

 stump was completely covered with rich brown tufts. Board piles, posts 

 and sides of old buildings yielded many fine specimens. Some species 

 fruited on grass blades and leaves, which were in close proximity to the 

 old logs in which the Plasmodia grew. Some of the best specimens we 

 obtained came from an old charred stump on the campus. The sporangia 

 almost always occur in very exposed places. This, together with their 

 large size and' abimdance. makes the discovery of them comparatively 

 easy. 



Many and careful attempts were made at germinating the spores of 

 the different species. None was successful, although several kinds of 

 media were used. Besides water, concoctions of rotten wood, on which 

 the specimens grew, were tried, but all without success. 



