PHYSARUM.] PHYSARACEiE. 00 
are seated on short white stalks. The abundant lime in the capillitium 
and psendo-columella are varying characters, but are unusually pro- 
nounced in this specimen. The spores are purplish-brown, minutely 
and closely spinulose, 9 to 10 /x diam. Prof. Macbride compares it 
with F. glaucum Phill., a synonym for P. compressum, and there does 
not appear to be any specific character by which it can be separated 
from that species. 
ITah. On dead wood, etc.— Shrewsbury (B. M. 115) ; Hitchin, Herts. 
(L:B.M.30); Linlithgowshire (K. 1499); Germany and Poland 
(Strassb. Herb.) ; Italy (B. M. 423) ; Ceylon (B. M. 419, 420) ; Australia 
(K. 1314) ; New Zealand (K. 1282) ; S. New Hampshire (L:B.M.30) ; 
?i. Iowa(B. M. 806); Texas (K. 1303) ; Cuba (K. 1350) ; Juan Fernandez 
(K. 510) ; Paraguay (Paris Herb.) ; Nicaragua (B. M. 1010). 
22. P. didermoides Rest., Men., p. 97, fig. 87 (1875). Plas- 
modium? Total height 0-5 to 1-3 mm. Sporangia ovoid, erect, 
stipitate or sessile, crowded, about 0-8 mm. high, 0*5 mm. broad, 
white, or dark grey above from the falling away or discontinuance 
of the outer calcareous crust ; sporangium-wall of three layers, 
the outer a dense deposit of vp^hite lime-granules, deciduous, the 
middle layer a delicate colouiiess membrane with scattered lime- 
granules, closely combined with an inner purplish, hyaline, areo- 
lated, thicker layer. Stalk variable in length and thickness, or 
wanting, white, membranous, with innate deposits of lime-granules, 
not containing refuse matter, rising from a pKcate white hypo- 
thallus. Columella none. Capillitium consis"ting of numerous 
rounded or somewhat angular white lime -knots connected by short, 
seldom branching, hyaline threads, which are purple at the attach- 
ments to the sporangivim-wall. Spores very dark purple-brown, 
nearly smooth or minutely spinulose, 10 to 13 jx diam. — Cooke, 
Myx., p. 11 ; Mass., Mon., p. 291 ; Macbride, in Bull. Nat. Hist. 
Iowa, ii., p. 154. Spumaria} didermoides Pers., Syn., Addenda, 
p. xxix (1801). Physarum lividum (3 licheniforme E,ost., Mon., 
p. 95 ; Mass., Mon., p. 304 (in part). Physarum cinereum var. 
ovoideum Sacc, in Michelia, ii., p. 334; Sacc, SylL, vii., p. 344; 
Mass., Mon., p. 299. 
Plate XIX., A. — a. sporangia, x 20; h. capillitium, with fragment of 
sporangium-wall and spores, x 280 ; c. spore, x 600 (Italy). 
P. cinereum var, ovoideum Sacc. on Ailanthus glandulosa (B. M. 432) 
is a short-stalked form of P. didermoides, the sporangia arising from 
a white membranous hypothallus. P. lividum var. licheniforme Rost., 
parts of the type of which from Schweinitz' Herb, are in the 
Strassburg and Kew collections (K. 1249), is a sessile form of P. 
didermoides. 
Hah. On dead wood, leaves, etc.— King's ClifE, Norths. (K. 1252) • 
Lyons, France (B. M. 432) ; Germany (Paris Herb.) ; Italy (K. 101) •' 
Natal (K. 8) ; Ceylon (B. M. 420) ; Iowa (B. M. 809) ; N. Carolina 
(B. M. 998) ; Ohio (L:B.M.31). 
23. P. cinereum Pers., in Rcimer, N. Mag. Bot., i., p. 89 (1794). 
Plasmodium watery white, among dead leaves. Sporangia 
sessile, subglobose, pulvinato, oblong or plasm odiocarps, scattered 
or crowded, contorted and confluent, 0-3 to 0-5 mm. broad, white 
or cinereous, more or less warted or veined; sporangium- wall 
