Physarum 61 



brown, yellowish, or white, with either refuse matter or lime. 

 Capillitium a network of hyaline threads with numerous small, 

 usually angular, white lime-knots. Spores purple-brown, spinu- 

 lose, 9-12 /x diam. 



Type locality: New York. 



Habitat: On dead wood. 



Distribution: Common and abundant in the eastern United 

 States; Colorado, Ontario, Quebec, and probably elsewhere in 

 North America. 



Illustration: Lister, Mycetozoa ed. 3. pi. 40, fi^^s. c-e, as 

 P. connatum. 



This species as described represents a center around which 

 are innumerable forms differing in particulars of size, shape, stalk, 

 lime and lime-knots, even to the size, color, and roughness of the 

 spores. Usually the spores are not as dark in color as those of 

 P. compressum, but the color is an unreliable character, as it is 

 inconstant. In late September and in October, and in cotton- 

 wood areas, P. notahile appears in great abundance, covering 

 almost every decaying log with large colonies. Single colonies 

 may have stalked and sessile sporangia, plasmodiocarps, and all 

 sorts of variations. It is advisable to study the species on such 

 occasions in order to understand its relations to P. compressum 

 and P. nutans, with each of which it is connected by intermediate 

 forms. Developments in the earlier months of the season are 

 much smaller, rarely more than two or three inches across, and are 

 usually confined to a single phase. P. notabile is connected with 

 P. compressum through the sessile sporangia and plasmodiocarps, 

 but can be distinguished by the firmer appearance and angular 

 lime-knots. The sporangia and plasmodiocarps of P. compressum 

 have crusty walls and rounded lime-knots. The approach to 

 P. nutans is through vars. robustum and leucophaeum of the latter 

 species. These latter are also centers and variable, but generally 

 show some resemblance to P. nutans, and usually have paler 

 spores than P. notabile. Flattened phases of P. notabile, when 

 sessile, may look like Badhamia affinis. The sporangia may also 

 resemble Badhamia panicea, if sessile, with a Badhamia-like capil- 

 litium, and a pseudo-columella, which is present sometimes. 

 Altogether, the species is a difficult one, and requires considerable 

 study of much material in order to understand it, and particularly 

 in the line approaching P. nutans. There are specimens which 

 it is impossible to place definitely, as in many instances there are 



