60 
ENDOSPORE/H;, 
[PHYSARUM. 
Plate XXI., k.—a. sporangia, var. a, x 20 ; h. capillitium, with fragment 
of sporanginm-wall showing calcareous discs, and spores, x 280 ; c. spore, 
X 600 (England), 
B. — a. sporangia, var. /3, x 20; J. capillitium and spores, x 280 (England). 
Glycerine mountings of a. genuinum show, dispersed in the sporangium- 
wall, flattened disc-shaped crystalline bodies with a radiating structure, 
measuring 10 to 20 diameter, such as are also found in the sporangium- 
wall of P. psiitadnum and Crateriuvi leiicocephulum. They do not 
appear to be present in vars. /3 and y of P. virescens. Didymium 
terrigenum Berk. & Curt., from Carolina (B. M. 575), is given by Rost. 
as a synonym for Physarum cinereuvi Rost., Mon., App., p. 9. The 
specimen is in a poor condition, but the character of the sporangia 
and spores and the orange-yellow lime-knots places it under P. virescens. 
The specimen from Iowa (B. M. 1011), to which Prof. Macbride applied 
the name P. auriscalpium Cooke {l.c.\ is P. virescens y nitens. 
Hah. On dead leaves, grass, etc. — a. Epping Forest, Essex (L:B.M. 
37). /3. Lyme Regis, Dorset (L:B.M.37) ; a. France (Paris Herb.) ; 
a. Germany (B. M. 413) ; /3. Hungary (K. 1529) ; a. Dorfhalden (B.M. 
861). y. Maine (L:B.M.37) ; a. Massachusetts (L:B.M.37) ; y. Iowa 
(B. M. 1011). 
29. P. insequale Peck, in Rep. N. York Mus. Nat. Hist., xxxi., 
Bot., p. 40 (1879). Plasmodium? Sporangia subglobose, 0"3 to 
0'7 mm. diam., sessile, or elongated and confluent forming plas- 
modiocarps, gregarious, yellowish-red, brick-red, rosy-red, or ■vthen 
little lime is present pale bluish spotted with red, somewhat 
rugose, rupturing irregularly ; sporangium- wall membranous, 
colourless above, yellow at the base, with innate clusters of red or 
yellow lime-granulcs. Columella none. Capillitium a network 
of delicate hyaline colourless or pale yellow threads, with rounded 
lime-knots varying in shape and size, each knot with a red centre 
surrounded by yellow round lime-granviles 1 to 3 /a diam. Spores 
pale violet-brown, almost smooth, 6 to 9 /x diam. — Didymium 
lateritium Berk. & Eav., in Grev., ii. (1873), p. 65. Physarum 
Ditmari y lat&ritium Rost., Mon., App., p. 9. Didymium croceo- 
flavum Berk. & Br., in Linn. Journ., xiv. (1875), p. 84. Phy- 
sarum Ditmari ^ croceoflavum Rost., Mon., App., p. 9. Physarum 
chrysotrichum Mass., Mon., p. 300 (in part). 
Plate XXII., B.— o. sporangia, x 20; h. capillitium with fragment of 
sporangium-wall and spores, x 280 ; c. spore, x 600 (S. Carolina : 
Berkeley's type of D. lateritium^. 
Intermediate between P. rubiginosum and P. virescens ; from orange 
forms of the latter it differs in the scattered habit of its sporangia, 
and from both species in the curious structure of the rounded lime- 
knots. 
Hah. On dead leaves, wood, etc.— Ceylon (B. M. 414) ; Georgia, 
U.S.A. (B. M. 898) ; S. Carolina (B. M. 898, 899) ; Philadelphia 
(L:B.M.38) ; Ohio (L:B.M.38). 
30. P. rubiginosum Fries, Symb. Gast., p. 21 (1817). Plas- 
modium? Sporangia subglobose, 0-5 to 0-8 mm. diam., sessile, 
gi-egarious or crowded, smooth or rather rough, orange or deep 
