58 
ENDOSPOEEili. 
[ PHYS'ARUM. 
The uncompressed sporangia Avith the outer wall nearly free from 
the smooth purplish inner wall characterises this species, and dis- 
tinguishes it from P. bivalve and P. coinpressiim, its nearest allies. 
Ilab. On dead leaves, etc. — Wanstead, Essex (L:B.M.;-34) ; Flitwick, 
Beds. (L:B.M.34) ; Germany (B. M. 512). 
26. P. contextum Pers., Syn., p. 168 (1801). Plasmodium 
yellow. Sporangia subglobose, ovoid, erect, 0-4 to 0*6 mm. diam., 
sessile or reniform and elongated on a broad base, crowded, often 
angled by mutual pressure, rounded or flattened above, smooth, 
yellowish-white or ochraceous ; sporangium-wall double, the outer 
layer thick with dense deposits of lime, often breaking away in 
the upper part from the thin colourless inner layer. Columella 
none. Capillitium with scanty hyaline threads and numerous 
large ii'regularly branching white lime-knots. Spores dark violet- 
brown, spinulose, 10 to 13 ju. diam. — Post., Mon., p. 109 ; Cooke, 
Myx. Brit., p. 13; Mass., Mon., p. 303 (in part); Macbride, in 
Bull. Nat. Hist. Iowa, ii., p. 157. Diclerma contextum Pers., Obs. 
Myc, i., p. 89 (1796); Fr., Syst. Myc, iii., p. 111. Diderma 
ochroleucum Berk. & Curt., in Grev., ii., p. 52. Physarum con- 
glomeratum Mass., Mon., p. 304. 
Plate XX., A. — a. sporangia of two forms, x 20 ; J. capillitium and spores, 
X 280 ; c. spore, x 600 (Germany : Rostafinski's type). 
The type of Diderma ochroleucum Berk. & Curt., from Pennsylvania 
(K. 15P)3), is typical P. contextum. 
Iluh. On dead leaves, sticks, etc. — Lyme Regis, Dorset (L:B.M.35); 
near Birmingham (L:B M.35); France (K. 365) ; Germany (B. M. 418) : 
Sweden (K. 1277); Poland (Strassb. Herb.); Iowa (B. M. 808); 
Mass., U.S.A. (L:B.M.35). 
27. P. conglomeratum Post., Mon., p. 108, figs. 73, 79, 90 
(1875). Plasmodium? Sporangia subglobose, sessile on a broad 
base, densely aggregated on one plane, angled by mutual pressure, 
0'3 to 0'5 mm. broad, yellow or brownish- white, mottled with 
paler shades; sporangium -wall double, the inner layer of the 
convex upper wall having translucent, pale yellow, curved, 
thickened areas, with a vitreous fracture ; the outer layer thick, 
consisting of easily crumbling yellow lime-granules ; the wall 
below thin with the two layers less distinct. Capillitium of deli- 
cate branching hyaline threads, with numerous white or yellowish, 
branching, often confluent lime -knots. Spores pale violet-brown, 
almost smooth, 8 to 10 /x, diam. — List., in Journ. Bot. 1891, 
p. 259, PI. cccviii., fig. 1, Diderma conglomeratum Syst. Myc, 
iii., p. Ill (1829). Physarum Rostafinskii Mass., Mon., p. 301. 
Plate XX., B. — a. sporangia, x 20 ; h. capillitium, with fragment of 
sporangium-wall, showing vitreous structure (&') and spores, x 280 ; c. spore, 
X 600 (Germany : Rostafinski's type). 
Distinguished from P. contextum. by the pale, nearly smooth, and 
smaller spores, and by the vitreous structure of the inner wall of the 
upper part of the sporangium. Rostafinski's type specimens of P. 
comjlomeratum from Germany (Strassb. Herb.) and from Sikkim 
