76 Mycetozoa of North America 



Plasmodium orange-yellow (Lister). Sporangia gregarious, 

 rarely clustered, sessile, subglobose, 0.3 to 0.7 mm. diam., or 

 forming short terete plasmodiocarps, rarely branched or netted, 

 scarlet or orange-red; sporangial wall an outer crust of compacted 

 scarlet or yellow lime-granules, lightly affixed, separating and 

 breaking away in flakes from the inner, membranous wall. 

 Capillitium a network of slender, colorless or pale yellow threads, 

 with rounded lime-knots, orange or yellowish, usually with red 

 centers. Spores pale brownish lilac, 7-9 ju diam., almost smooth. 



Type locality: South Carolina. 



Habitat: On dead wood and leaves. 



Distribution: Widely distributed and common in the United 

 States and Canada. 



Illustration: Lister, Mycetozoa ed. 3. pi. 60. 



This species forms small, solitary colonies. As described and 

 restricted, it is remarkably constant in characters with hardly any 

 obscure forms. From P. ruhiginosum it is distinguished by the 

 smaller, rounded lime-knots, usually with red centers, and the 

 flaky wall. 



59. Physarum luteolum Peck, Rept. N. Y. State Mus. 30: 50. 

 1878. 



Physarum virescens Ditm. var. nitens Lister, Mycetozoa 59. 1894. 



Plasmodium? Sporangia gregarious or clustered but not 

 heaped, sessile, subglobose, 0.4 to 0.8 mm. diam., rugulose, rarely 

 smooth, bright yellow; sporangial wall membranous, with included 

 yellow lirr>e-granules. Capillitium a network of hyaline threads 

 with numerous small, yellow, angular or branching lime-knots. 

 Spores pale lilac, minutely spinulose, 8.5-11 ju diam. 



Type locality: New York. 



Habitat: On dead leaves. 



Distribution: Colorado, *Iowa, Massachusetts, New Hamp- 

 shire, New Jersey, New York, Ontario, Pennsylvania, Quebec. 



Illustration: Lister, Mycetozoa ed. 3. pi. 62, figs, a-c, as 

 P. virescens var. nitens. 



This species forms small, solitary colonies in dry places, and is 

 not rare. It is not heaped like P. virescens, although occasionally 

 clustered, and is much larger with a brighter color. Its general 

 appearance is more like P. cinereum, except that it is yellow. 



