ARCYRIA.] ARCYRIACE.E. 191 



curved, stipitate, clustered, rising from a common membranous 

 hypothallus, 0'6 to 1'5 mm. high, O3 to O5 mm. broad, dull crimson; 

 sporangium-wall evanescent above, with the exception of a few 

 well defined rounded plates, which are papillose on the inner 

 side, with a smooth margin; cup membranous, papillose with a 

 smooth rim. Stalks varying in length, usually very short, weak, 

 filled with spore-like cells, pale red. Capillitium a very elastic 

 network of pale red, nearly terete threads, 3 to 5 /x diam., 

 expanding into a drooping column three or four times the length 

 of the sporangium. ; thickenings in the form of sharp spines 1 to 

 3 \L long, more or less equally distributed, though the spiral 

 arrangement is generally shown ; threads attached at numerous 

 points to the persistent plates of the sporangium-wall, with few 

 attachments to the cup ; free ends sometimes present with spinulose 

 tips. Spores pale red, nearly smooth, marked with few scattered 

 warts, 7 to 8 //, diam. Cooke, Myx. Brit., fig. 196; Lister, in 

 Journ. Bot. (1891), p. 266 ; Macbride, in Bull. .Nat. Hist. Iowa, 

 ii., p. 125; Mass., Mon., p. 147. Hemiarcyria fuliginea Cooke 

 & Massee, in Grev., xvi., p. 74. Arcyria fuliginea Mass., Mon., 

 p. 169. Arcyria magna Hex, in Proc. Acad. Nat. Sci. Phil. 

 (1893), p. 364. 



Plate LXIX.. B. a. sporangia and expanded capillitium. x 9 ; b. shield- 

 like persistent portion of sporangium-wall, with capillitium attached, 

 x 180 : c. capillitium with portion of cup of sporangium- wall, and spore, 

 x 600 (England). 



A specimen in Strassb. Herb, marked " (Erstedt " is identical with 

 the English gatherings of this species, as are also specimens from the 

 United States received from Dr. Rex under the name of A. (Er*tedt'ri. 

 Although nearly allied to A. flaua, it differs in the colour, and in the 

 spines on the capillitium being more slender and closely set and more 

 evenly distributed ; it also differs in the presence of the well defined 

 persistent portions of the sporangium-wall, which appears to be a 

 very constant feature. Specimens received from different parts of 

 the world possess the same characters with but little variation. The 

 type specimen of Hemian.'jji'ia fidiginea Cooke & Mass., from N". S. 

 Wales (K. 154), has the capillitium attached to persistent papillose 

 plates of the sporangium-wall, and is similar to the Lyme Regis 

 gatherings of A. (Erstedtii, except in the colour, which is now fuliginous- 

 brown. The constrictions and ovoid swellings in the capillitium, 

 mentioned by Rostafinski as characteristic of this species, are sometimes 

 met with in Lyme Regis gatherings ; they frequently occur in 

 A. incarnata and other Arcyrice, and cannot be held to be of specific 

 value. 



Arcyria magna Rex, and A. magna var. rosea Rex, are represented 

 by type specimens in the Museum (L:B.M.161) ; the expanded columns 

 of capillitium are of the same form and dimensions as in A. CErstedtii, 

 taking for comparison five growths of that species which developed 

 from white plasmodium during two successive years on a fir-log at 

 Lyme Regis. The two forms named as above were gathered from 

 one log of timber, and though var. rosea is brighter in colour than the 

 other, they are evidently the same species ; the sculpture on the 

 threads of the capillitium does not differ from that of the Strassburg 

 specimen referred to more widely than frequently appears in different 



