CHONDRIODERMA.] 
PHYSAKACEiE. 
77 
globose, sessile, crowded, 0-5 to 1 mm. diam., seated usually on a 
strongly developed white hypothallus, smooth or rugose, white ; 
sporangium-wall of two layers, the outer thick, fragile, composed 
of globular lime-granules 1 to 2 /a diam., often crumbling away 
from the membranous, more persistent inner layer, _ sometimes 
inseparable. Columella convex or hemispherical, white or pale 
flesh-coloured. Capillitium of slender, flexuose, purplish threads, 
branching at an acute angle and somewhat anastomosing. Spores 
violet-brown, spinulose, 8 to 11 /x diam.— Cooke, Myx. Brit., 
p. 38. Bidymium spumarioides Fr., 8jmh. Gast., p. 20 (1818); 
Mass., Mon., p. 232. Physarum stromateum Link, Handb., iii., 
p. 409 (1833). Chondrioderma stromateum E,ost., Mon., App., 
p. 18. Chondrioderma virgineum Mass., Mon., p. 207. 
Plate XXIX., B.— a. sporangia, x 20 ; 5. capillitium, with fragment of 
sporangium-wall and spores, x 280 ; c. spore, x 600 (England). 
The type specimen of G. vircjineum Mass. (K. 560) is a frequent 
form of G. spumarioides without hypothallus ; the capilUtium in some 
sporangia is normal and without expansions. The type specimen of 
C. stromateum Rost. in the Strassb. Herb, is from Lochem (leg. Spree, 
Rab. Fung. Eur., 432) ; a part of this gathering is in the British 
Museum (B. M. 515) ; it does not appear to present any character by 
which it can be separated from C. spumarioides. 
Hah. On dead leaves,etc. Common. — Lyme Regis, Dorset (L :B.M.52) ; 
France (K. 37) ; Germany (B. M, 515) ; New York (B. M. 886) ; 
Mass., U.S.A. (L:B.M.52). 
2, C. subdictyospermum Rost., Mon., App., p. 16 (1876). 
Plasmodium ? Sporangia subglobose, sessile, crowded, 0-3 to 
0*5 mm. diam., snow-white, seated on a well-developed white 
hypothallus; sporangium-wall thick, fragile, composed of an 
outer crust of globular lime-granules 2 /x, diam., with a delicate, 
membranous, inseparable inner layer. Columella hemispherical 
or subglobose, white. Capillitium of somewhat rigid, violet-brown, 
sparingly branched threads. Spores violet-brown, reticulated 
with raised ridges or with broken bands, forming a margin about 
2 ju, broad; 10 to 12 /x diam. — Didymium dealbatum Berk. & 
Curt., in Herb. Chondrioderma dealhata Mass., Mon., p. 207. 
Plate XXX., B. — d. sporangia, x 20 ; e. capillitium and spores, x 280 ; 
/. spore, X 600 (Venezuela, Rostafinski's type) ; g. spore, x 600 (Cape). 
This species appears to be allied to C. spumarioides^ differing 
essentially in the spores. It is represented by two gatherings. One 
is from Venezuela, named Didymium dealbatum Berk. & Curt. 
(B. M. 570 ; K. 1522) ; this is the type given by Rostafinski (Mon., 
App., p. 16), and accurately described as having spores provided with 
protuberances either irregularly disposed or combined into an incomplete 
net. The other gathering is in the Kew collection (K. 466), named 
Didymium, physaroides, Cape 198 ; in this specimen the spores are more 
perfectly reticulated, and, except in colour, resemble those of Trichia 
favoginea^eva. ; the capillitium is also more flexuose. 
Hab. On moss.— Cape (K. 466) ; Venezuela (B. M. 570). 
