226 A MonograpJi of the Alyxogastres. 



Didymium squ.nimUosnm, Fr., S. M., iii,, 118; Eng. Fl., v., 



312; Cke., Hdbk, No. 1122. 

 DifJymium ncghctum, B. and Br., Ceylon Fungi, No. 747. 

 Didymium aastralc, Berk., Hdbk., Flor. Nov. Zealand, p. 191. 



Var. virgincnm, Mass. 



Scattered, or in clusters of two or three ; sporangia subglobose, 

 flattened and slightly umbilicate below, external crust of lime 

 pure white, rugulose and crumjdcd but continuous; stem lohite, 

 stout, equal to sporangium or shorter, expanding at the base 

 into a small wrinkled hypothallus ; mass of capillitium and 

 spores blackish; columella siihglohosc or hemisjyJicrical, white or 

 ycllmvish, rugulose; threads of capillitium copious, radiating 

 from the columella to the wall of the sporangium, 3 — 4 jj. thick 

 at the base, a little thinner upwards, often flexuous, sparingly 

 branching at an acute angle, and sometimes connected laterally, 

 with scattered, small, elliptical swellings, pale dingy violet or 

 brownish, sometimes almost colourless ; spores globose, epispore 

 rather thick, brownish- violet, minutely verruculose, 10 — 13 ii 

 diameter. 



On leaves, wood, &c. 



Britain (Scarborough, Carlisle, Epping Forest) ; Italy. 

 (Type in Herb., Kew.) 



Sporangia 1 — 1"5 mm. diameter. The outer coat of lime is 

 very much crumpled, with prominent irregular ridges, but does 

 not become broken up into dctaclicd particles as is usual in 

 the genus Didymium. 



Didymium microcarpon, Rost. (hgs. 44, 45). 



S'porangia glohose, at first with an external continuous white 

 crust of lime, which soon becomes broken up into minute 

 glistening particles, resting on the inner dark membrane, more 

 or less umbilicate below, stein slender, slightly attenuated ufumrds, 

 blackish or rufous, longitudinally rugulose, expanding at the 

 base into a small subcircular hypothallus, straight or slightly 

 curved above, generally cd)o^it twice the length of the s^iorangium ; 



