ARCYRIA.] 
ARCYRIACE/E. 
191 
curved, stipitaie, clustered, rising from a common membranous 
hypothallus, 0-6 to 1-5 mm. high, 0-3 to 0-5 mm. broad, dull crim&t)n; 
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 ju, long, more or less equally distributed, though the spiral 
arrano-ement is generally shown j 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. Nsit. 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 Rex, in Proc. Acad. Nat. Sci. Phil. 
(1893), p. 364. 
Plate LXIX., B. — a. sporangia and expanded capillitium, x 9 ; Z». 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 " (ErstecU " 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. CErstedtii. 
Although nearly allied to A . flava, 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-waU, 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 Hemiarcyria fuliginea 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. (Erstediii, 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 yl. 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 
