PHYSARUM 79 



habit and external appearance are different; the stipe notably long, 

 clumsy, surcharged with lime; a very singular form. 

 Castillo, Nicaragua. 



55. Physarum notabile Macbr. 



N. A. Slime-Moulds ed. 2. 80. 1922. 

 PI. VI, Figs. 103, 104. 



1874. Didymium connatum Pk., Rept. N. Y. State Mus. 26 : 74. 

 1879. Physarum polymorphum (Mont.) Rost. ex Peck, Rept. N. Y. State Mus. 

 31 : 55, non Rost. 



1893. Physarum kucophceum Fr. ex Macbr., Bull. Lab. Nat. Hist. Iowa 2 : 156, 

 non Fr. 



1894. Physarum compressum Alb. & Schw. ex Lister, Mycetozoa 53, in part. 

 1896. Physarum connexum Lk. ex Morg., Jour. Cin. Soc. Nat. Hist. 19 : 20, in 



part. 

 1896. Physarum confluens Pers. ex Morg., Jour. Cin. Soc. Nat. Hist. 19 : 22. 

 1899. Physarum nefroideum Rost. ex Macbride, N. A. Slime-Moulds 41, in 



part. 

 1911. Physarum connatum (Pk.) Lister, Mycetozoa ed. 2. 71, non Ditm., non 



Schum. 



Sporangia gregarious, sessile, stipitate, or even plasmodiocarpous; 

 when stipitate, depressed, varying at times to irregular reniform in 

 the same colony, or globose; peridium strongly calcareous, cinereous- 

 white; stipe variable, generally tapering upward, always distinctly 

 deeply plicate-furrowed throughout, in color dark, opaque, sometimes 

 touched with white or gray, or white from a coating of calcareous 

 granules; capillitium abundant, the white lime-knots, varying in size 

 and shape, connected by rather long hyaline threads, with here and 

 there an empty node; spore-mass black, by transmitted light dark, 

 sooty brown, minutely papillose, 10-11.5 /jl. 



This remarkable species, while not at all difficult of recognition to 

 one familiar with its phases, is withal very difficult to define. Nor- 

 mally stipitate, it often shows from the same plasmodium all sorts of 

 forms, the shape of the fructification dependent apparently upon ex- 

 ternal conditions prevalent at the time. The amount of calcium also 

 varies, especially in the capillitium, where there is usually much, with 

 a tendency to the formation of something like a pseudocolumella; 

 the outer net in such cases nearly destitute. The calcium in the stipe 

 also varies; the black or brown stipes are, of course, free from it; the 

 gray or white, calcareous. 



Eastern United States and Canada, Brazil; Europe. 



Physarum compressum Skvortz. non Alb. & Schw., Phil. Jour. Sc. 

 46 : 86, 1931, agrees, so far as the description goes, with some forms 



