PHYSARUM.] PHYSAEACB^. 45 



capillitium. Capillitium abundant, of extremely delicate branching 

 and anastomosing threads without expansions at the axUs, some- 

 what persistent, and of a pale bluish colour after the dispersion of 

 the spores j lime-knots white, few, small, fusiform except in the 

 central globular cluster. Spores violet-brown, almost smooth, 

 7 to 9 ju diam. — Tihnadoche compacta Wing., in Proc. Acad. Nat. Sc. 

 Phil. 1889, p. 48; Mass., Mon., p. 332. Lepidoderma stellatum 

 Mass., Mon., p. 252. 



Plate X., B. — a. sporangia, x 20 ; 5. stalk and cipillitium with pseudo- 

 columella and fragment of sporangium- wall, showing compacted and sharply- 

 defined clusters of lime-granules, x 80 ; c. capillitium and spores, x 280 ; 

 d. spore, x 600 (Dominica). 



An excellent account of this species is given by Mr. Wingate (I.e., 

 p. 48). He describes the sporangium- wall as splitting on maturity in a 

 floriform manner, which is a marked character in the specimens at 

 hand ; his description of the stalk as " yellowish-white with a brown 

 or blackish base " appears to be correct for the American gatherings. 

 In a flue specimen of P. compactum in the Kew collection from 

 Dominica (Ramage), K. 567, marked Lepidoderma stellatum Mass., the 

 stalks are pure white with a chalky section to the base. The specimen 

 from French Guiana in the Paris Museum under the name Phjsa/rum 

 leucophceum is precisely similar to that from Dominica in the large 

 opaque white lime-spots on the sporangium-wall and in the pure white 

 stalks. The type of Didymium columbinum Berk. & Curt. {Tilmadoche 

 columhina Rost., Mon., App., p. 13), Venezuela (K. 1428), appears to 

 be this species, but nothing now remains of the specimen but a few 

 stalks and a little of the extremely delicate capillitium. 



Hah. On dead wood. — Borneo (L:B.M.20) ; Dominica (K. 567) ; 

 Philadelphia (B. M. 875, L:B.M.20) ; Ohio (L:B.M.20) ; French 

 Guiana (Paris Herb.). 



11. P. roseum Berk. & Br., in Journ. Liun., xiv., p. 84 (1873). 

 Plasmodium ? Total height 1 mm. Sporangia globose, ff-4 mm. 

 diam., stalked, gregarious, nearly smooth, bright rose-coloured ; 

 sporangium-wall membranous, with innate clusters of purple-red 

 lime-granules. Stalk erect, slender, subulate, reddish-brown, 

 translucent, longitudinally rugose. Columella none. Oapillitium 

 a loose network of delicate pale lilac hyaliae threads, with rather 

 few large, irregularly branching, purple-red lime-knots. Spores 

 reddish-lilac or reddish-brown, minutely spinulose, 7 to 10 /j, diam. 

 Eost., Mon., App., p. 10; Mass., Men., p. 294. 



Plate XI., A. — a. sporangia, x 20 ; i. capillitium with fragment of 

 sporangium-wall and spores, x 280 ; v. spore, x 600 (Borneo). 



This species differs from P. pulcherrimum in the large lime-knots 

 and the translucent stalk. 



ffab. On dead wood.— Ceylon (K. 1758) ; Borneo (L:B.M.21). 



12. P. Xewtoni Macbride, in Bull. Nat. Hist. Iowa, vol. ii., 

 4, p. 390 (1893). Plasmodium? Sporangia shortly stalked or 

 sessile, globose, about 0-5 mm. diam., or flattened and umbilicate 

 above, violet-purple, smooth, opaqiie ; sporangium-wall mem- 

 branous above, with innate deposits of purple lime-granules, 

 rugose and thickened towards the base, where it is deep purple 



