82 
ENDOSPORB^. 
[CHONDRIODERMA. 
Sub-genus 2. — Leangium. Sporangia stipitate or sessile; 
sporangium-wall of two closely connected layers (which do not 
separate, except in G. Sauteri) ; the outer cartilaginous, more or 
less charged with innate minute lime-granules ; the inner mem- 
branous, often dehiscing in revolute lobes from the naked globose 
mass of spores. 
9. C. Trevelyani Host., Mon., p. 182 (1875). Plasmodium? 
Total height 1 to 1-5 mm. Sporangia globose or subellipsoid, 
sessile or shortly stalked, verrucose or nearly smooth, 1 mm. 
diam., reddish or orange-brown ; sporangium-wall splitting irre- 
gularly or in unequal, revolute, petal-like lobes, white on the 
inner side : of three inseparable layers, the outer one cartilagi- 
nous, brown ; the inner delicately membranous, attached to the 
threads of the capillitium ; the middle layer thick, composed of 
coarse irregular crystals of lime. Stalk equal, furrowed, 0*1 to 
0"5 mm. high, 0"1 to 0*15 mm. thick, of the colour of the 
sporangium. Columella none. Capillitium profuse, purple or 
purplish-brown, somewhat rigid, forming a network with dark 
bead-like thickenings at the nodes and on the threads, rarely 
slender, with few thickenings. Spores dark violet-brown, spinu- 
lose, 10 to 13 /X diam. — Cooke, Myx. Brit., p. 40 ; Mass., Mon., 
p. 202. Leangium Trevelyani Grev., Scot. Crypt. Fl., tab. 132 
(1825). Diderma Trevelyani Fr., Syst. Myc, iii., p. 105. Ghon- 
driodei-ma (Erstedtii Eost., Mon., p. 184, figs. 154, 157; Cooke, 
Myx. Brit., p. 41 ; Mass., Mon., p. 203. Diderma geasteroides 
Phill., in Grev., v., p. 113. Ghondrioderma geasteroides Phill., in 
Mass., Mon., p. 201. Diderma laciniatum Phill., I.e., p. 113. 
Plate XXXII. , B.—a. sporangia, x 20 ; b. capillitium and spores, x 280 ; 
c. fragment of sporangium-wall showing the cartilaginous and crystalline 
layers, x 280 ; d. spore, x 600 (California ; type of Diderma geasteroides 
Phill.) ; e. sporangium, x 20 (Shrewsbury, England). 
The crystalline middle layer of the sporangium- wall separates this 
from all other species of the Leangium group. The type specimen 
of C. Trevelyani described and figured under the name of Leangium 
Trevelyani in Greville's Scottish Crypt. Flor., tab. 132, is in the Edin- 
burgh Herbarium ; it is sessile onMnium undulatum, and was gathered by 
W. C. Trevelyan, Esq., who also sent specimens to Mr. Sowerby. The 
specimen named Diderma Trevelyani, "Sowerby Herb." (K. 1478), 
is on Milium undulatum, and is no doubt that referred to. Greville 
speaks of and figures a " very minute columella " ; he was evi- 
dently mistaken on this point, and Berkeley in describing Trevelyan 's 
gathering states : "I find no trace of a columella ; the bottom of 
the peridium within is perfectly even." Examination of the type 
in the Edinburgh collection confirms Berkeley's statement. The 
specimen from Jedburgh (K. 1477) is marked by Rostafinski 
Ghondrioderma Oerstedtii, and is given by him as a type of that species 
(Rost., Mon., App., p. 21) ; it has the characteristic capillitium and 
sporangium-wall of Greville's type. These characters are also present 
in Diderma r/easteroiden Phill. and D. laciniatum Phill., from California, 
in Herb. Phillips, These three specimens are clearly the same species 
as C, Trevelyani. 
