134 ENDOSPOREAE [DIDYMIUM 



those of the usual form. Chondrioderma Cookei Rost., of which the 

 type from Cheshire on leaves of Tussilago is represented both in Strassb. 

 Herb, and Brit. Mus. (B.M. 137), is also the present species ; it differs 

 from the usual form with sessile sporangia in having scanty deposits of 

 lime scattered in the form of minute spicules over the sporangium-wall ; 

 the capillitium is an irregular network of dull violet threads, with expan- 

 sions containing nodules of lime such as are of frequent occurrence in 

 imperfect developments both in this species and its allies ; the spores 

 are spinulose, 10 to 12 fx diam. 



Hub. On dead leaves, straw, etc. Very common. — Lyme Regis, 

 Dorset (B.M. 1347) ; Batheaston, Somerset (B.M. 37) ; Sydenham, 

 Surrey (B.M. 1070) ; Yorks (K. 462) ; Ireland (B.M. 2498) ; France 

 (K. 12) ; Germany (B.M. 530) ; Austria (B.M. 567) ; Italy (B.M. 433) ; 

 Portugal (B.M. 2499) ; Ceylon (B.M. 456) ; Java (B.M. 2500) ; New 

 Zealand (K. 1324) ; Japan (B.M. 2004) ; London, Canada (B.M. 

 1796) ; Washington State (B.M. 2502) ; Iowa (B.M. 2503) ; Kansas 

 (B.M. 2501); Vermont (B.M. 1349); Philadelphia (B.M. 1350); 

 South Carolina (K. 89) ; Antigua (B.M. 1666) ; Cuba (K. 542) ; 

 Brazil (B.M. 2504) ; Chili (Paris Herb.) ; Paraguay (Paris Herb.). 



10. D. anellus Morgan Myx. Miami Valley, 64, t. xii. 

 fig. 41(1894). Plasmodium colourless. Sporangia scattered, 

 sessile, usually orbicular, umbilicate above, 0*3 to 0*5 mm. 

 diam., often forming slender plasmodiocarps elongated into 

 links and chains, grey, or glossy brown from absence of lime ; 

 sporangium-wall membranous, colourless or purplish-brown, 

 sparingly beset with minute crystals of lime, at length dehiscing 

 in a circumcissile manner. Columella none. Capillitium 

 consisting of slender flexuose violet-brown threads, simple 

 or somewhat branched and anastomosing. Spores purplish- 

 grey or purplish-brown, minutely spinulose, 7 to 9 /x diam. — 

 Petch in Ann. Perad., iv. 349. D. effusum var. tenue Lister in 

 Journ. Bot., xxxv. 214 (1897). 



PI. 110. — a. sporangia (Essex); b. capillitium and spores with fragment of spor- 

 angium-wall ; c. spore. 



This species has been obtained from various parts of the world, 

 and, though closely resembling slender plasmodiocarp forms of D. 

 squamidosiim, appears to retain its distinctive characters, namely the 

 -circumcissile mode of dehiscence and the centrally depressed sporangia. 



Hab. On dead leaves. — Wanstead Park, Essex (B.M. 1716); 

 Witley, Surrey (B.M. 2506) ; Yorks (B.M. 2507) ; Ceylon (B.M. 2505) ; 

 Ohio (B.M. 2059). 



11. D. Wilczekii Meylan hi Bull. Soc. Vaud. Sci. Nat., 

 xliv. 290 (1908). Plasmodium grey. Sporangia scattered, 

 forming elongated curved or almost net-like plasmodiocarps, 

 1 to 2 mm. wide, 1 mm. to 3 cm. long, 0-3 to 0-5 mm. thick, 

 white, or glossy brownish-purjile when without lime ; sporan- 

 gium-wall dehiscing irregularly, membranous or somewhat 

 cartilaginous, colourless, yellowish or pale purplish, with 

 superficial deposits of minute stellate, rod-shaped, or nodular 

 crystals of lime, sometimes without any lime. Columella 



