52 THE NORTH AMERICAN SLIME-MOULDS 



by transferring the species to Physarum, and calling attention to 

 spore-dimensions. The fact is, the species in external appearance so 

 much resembles P. cinereum, that the unaided eye cannot distinguish 

 one from the other. Curiously enough, Rostafinsici describes the 

 form he had before him as "one of the rarest." Doubtless had he 

 gone back to his specimens of P. cinereum he had found plenty, for 

 in Europe it seems abundant everywhere. In this country it is P. 

 cinereum as now defined, that is rarer, although not uncommon. 

 From all connection with Badhamia, as representing B. panicea it 

 should, as would appear, be withdrawn once for all. 



4. Physarum sinuosum {Bull.) Weinm. 



Plate VIII., Figs. 6 and 6 a, and Plate XIX, Fig. 15. 



1791. Reticularia s'lnuosa Bulliard, Champ., p. 94; t. 446, Fig. 3. 



1796. Physarum bivalve Persoon, Obs. Myc, I., p. 6 ; t. III., Fig. 2. 



1828. Physarum sinuosum Wein., Fries teste, I. c. 



1828. Angioridium sinuosum Grev., Scot. Crypt. Fl., 310. 



1829. Physarum sinuosum Fries, Syst. Myc, III., p. 145. 

 1875. Physarum sinuosum (Bull.) Rost., Monograph, p. 112. 

 1892. Physarum sinuosum Rost., Massee, Mon., p. 305. 

 1894. Physarum bivalve Pers., Lister, Mycetozoa, p. 57. 



1896. Angioridium sinuosum (Grev.), Morg., Cin. Soc. Nat. Hist., p. 75. 

 1899. Physarum sinuosum (Bull.) Wein., Macbr., N. A. S., p. 28. 

 1911. Physarum sinuosum Wein., Lister, Mycetozoa, 2nd ed., p. 76. 



Sporangia distinct or plasmodiocarpous, the plasmodiocarp creeping 

 in long vein-like reticulations or curves, laterally compressed ; some- 

 times distinct and crowded, always sessile. Peridium double; the 

 outer thick, calcareous, fragile, snow-white; the inner delicate, the 

 dehiscence by more or less regular longitudinal fissure. Capillitium 

 strongly developed with abundant white, calcareous granules. Spores 

 smooth, dull violet, 8-9 ix. Plasmodium pale gray, or nearly white. 



Easily recognized at sight by its peculiar form, bilabiate and sinu- 

 ous. Apart from microscopic structure, perfectly described by Fries, 

 Syst. Myc, p. 145. Bulliard called it Reticularia sinuosa. Habitat 

 various, but not infrequently the upper surface of the leaves of living 

 plants, a few inches from the ground. The two sorts of fructifica- 

 tion often occur side by side, or merge into one another from the 



