Physarum 53 



29. Physarum straminipes Lister, Jour. Bot. 36: 163. 1898. 

 (N. Y. B. G. no. 10931, type material.) 



Plasmodium milk-white (Lister). Sporangia obovoid or 

 wedge-shaped, 0.7 mm. diam., grayish white, clustered or scat- 

 tered, on long or short stalks, two or more often borne on a single 

 stalk, or sessile and subglobose or irregularly ellipsoid; sporangial 

 wall colorless or pale purple, membranous, rather firm, with dense, 

 included clusters of lime-granules. Stalks straw-colored, trans- 

 lucent, often 2 mm. long, membranous or cartilaginous, flattened 

 or filiform, free from refuse matter, often continued below into a 

 strand-like hypothallus. Capillitium a persistent network of 

 stout, hyaline threads, with expansions at the axils, and numerous 

 white, rounded lime-knots, some of which often unite to form a 

 pseudo-columella. Spores purplish brown, marked with broad 

 patches of warts separated by smoother tracts, 10-11 fi diam. 



Type locality: England. 



Habitat: On dead leaves and straw. 



Distribution: *Oregon. 



Illustration: Lister, Mycetozoa ed. 3. pi. 42. 



30. Physarum pusillum (Berk. & Curt.) Lister, Mycetozoa ed. 2. 

 64. 1911. 



Didymium pusillum Berk. & Curt.; Berk. Grevillea 2: 53. 1873. 



Physarum calidris Lister, Jour. Bot. 29: 258. 1891. 



Physarum gravidum Morg. Jour. Cin. Soc. Nat. Hist. 19: 24. 1896. 



Plasmodium watery white (Lister). Total height 1 to 2 mm. 

 Sporangia scattered or gregarious, stalked, erect or inclined, sub- 

 globose or lenticular, usually umbilicate beneath, rarely obovoid, 

 0.4 to 0.6 mm. diam., rugulose, white with a reddish base; sporan- 

 gial wall membranous, colorless above, with clusters of included, 

 white lime-granules, scanty or dense, thickened and rufous at the 

 base. Stalk subulate or cylindrical, furrowed, 0.5 to 1.5 mm. 

 long, red-brown, usually free from refuse matter. Capillitium a 

 network of colorless, branching threads; lime-knots either few 

 and small, or large, numerous, and branching, or Badhamia-Vike. 

 Spores pale brownish lilac, almost smooth or marked with patches 

 of minute warts, 8-11 ju diam. 



Type locality: South Carolina. 



Habitat: On dead leaves, stems, twigs, and wood. 



