262 Mycetozoa of North America 



3. Perichaena corticalis (Batsch) Rost. Mon. 293. 1875. 



Lycoperdon corticate Batsch, Elench. Fung. 155. 1783. 



Perichaena populina Fries, Symb. Gast. 12. 1817. 



Perichaena marginata Schw. Trans. Am. Phil. Soc. II. 4: 258. 1832; Hagel- 



stein, Mycologia 29: 401. 1937. 

 Perichaena ochrospora Peck, Rept. N. Y. State Mus. 54: 156. 1901. (N. Y. 



B. G. no. 7975, type material.) 



Plasmodium watery gray (Lister). Sporangia crowded or 

 scattered, subglobose, ellipsoid, or forming bolster-shaped plasmo- 

 diocarps, sessile on a broad or narrow base, rarely short-stalked, 

 0.2 to 1 mm. diam., dark purple, purplish brown, gray or white, 

 dehiscing in broad, sinuose lobes, or horizontally with a convex 

 lid; sporangial wall of two layers, the outer cartilaginous, yellow- 

 ish brown, charged with brown granular matter, often intermixed 

 with or replaced by crystals of lime forming a gray or white cover- 

 ing; inner wall membranous, usually closely combined with the 

 outer. Capillitium often scanty or even lacking, consisting of 

 long or short, branched or simple, yellow threads 1.5-4 n diam., 

 irregularly compressed, angled and constricted, minutely warted 

 or marked with short spines and prominences, rarely smooth, 

 either attached to the sporangial wall or free. Spores yellow, 

 minutely and closely warted, 10-14 /x diam. 



Var. liceoides (Rost.) Lister, Mycetozoa ed. 2. 251. 1911. 

 Perichaena liceoides Rost. Mon. 295. 1875. 



Sporangia subglobose or bolster-shaped, shining iridescent 

 yellow, brown, blue, or purplish, minute, 0.1 to 0.5 mm. diam., 

 dehiscing irregularly; granular deposits of the outer translucent 

 sporangial wall scanty or wanting; capillitium often scanty or 

 none, rarely forming a network of nearly smooth threads; spores 

 10-15 fjL diam. 



Type locality: Germany. 



Habitat: On dead bark and wood. 



Distribution: Common throughout North America; var. 

 liceoides, Florida, New York. 



Illustration: Lister, Mycetozoa ed. 3. pi. 186. 



Occasional intermediate forms occur connecting this species 

 with P. chrysosperma and P. vermicularis. The species often 

 forms colonies with thousands of sporangia on the outside of bark, 

 and in these the dehiscence is by broad lobes and not by lids. 

 Sometimes when the lines of dehiscence are not clearly visible 



