198 
ENDOSPOREjE. 
[PERICHiENA. 
Hah. On dead wood and bark— Epping Forest, Essex (L:B.M.164) ; 
Lyme Regis, Dorset (L:B.M.164) ; Leicestershire (B. M. 69G) ; Glamis^ 
Scotland (B. M. 323) ; Belgium (B. M. 690) ; Germany (B. M. 688) ; 
Italy (B. M. 089) ; Poland fStrassb. Herb.) ; Australia (K. 153) ; 
Philadelphia (L:B.M.164; ; Ohio (L:B.M.164) ; S. Carolina (B. M. 
697, 986). ^ 
3. P. populina Fries, Symb. Gaster.,p. 12 (1817). Plasmodium 
watery-grey, in decaying bark. Sporangia globose, depressed, 
ellipsoid, or forming short broad plasmodiocarps, crowded, sessile 
on a broad or narrow base, rarely substipitate, 0-5 to 1 mm, 
diam., dark purple or purplLsh-brown, nut-brown, grey or white, 
dehiscing along definite lines, either horizontally with a convex 
lid or in broad sinuous lobes ; sporangium -wall of two layers, the 
outer cartilaginous, opaque, charged with brown granular matter 
intermixed with acicular or angular calcareous deposits which 
form a pruinose or crystalline covering in the grey and white 
sporangia ; inner layer membranous, usually closely combined 
with the outer. Capillitium scanty or almost wanting, consisting 
of slender, branched or simple, yellow threads, 1-5 to 4 /x diam., 
irregularly compressed, angled and constricted, minutely warted, 
rarely smooth ; attached to the sporangium-wall or free. Spores 
yellow, more or less minutely warted, 12 to 14 /x diam. — 
Lycoperclon corticale Batsch, Elench. Fung., p. 155 (1783). 
Perichcena corticalis E,ost., Mon., p. 293, fig. 188 ; Cooke, Myx. 
Brit., p. 78 ; Zopf, in Schenk, Handbuch der Botanik, iii., 2, 
p. 169; Blytt, Bidr. K. Norg., Sop. iii. (1892), p. 10; Macbride, 
in Bull. N"at. Hist. Iowa, ii., p. 120; Mass., Mon., p. 115. 
Trichia fusco-atra Sibth., Fl. Oxon, p. 407 (1794). FerichcBna 
fusco-atra Rost., Mon., p. 294 ; Cooke, Myx. Brit., p. 78. 
Licea pannoTum Qierik. (non Wallr.), Pringsb., Jahrb., iii., p. 407. 
Perichcena liceoides Rost,, Mon., p. 295 ; Mass,, Mon., p. 118. 
Oligonema Broomei Mass,, in Journ. R, Micr. Soc. (1889), 
p. 346 ; Mass., Mon., p. 172. 
Plate LXXII., A. — a. sporangia, x 20 ; b. capillitium and portion of 
sporangium-wall, x 280 ; c. capillitium and spore, x 600 (England). 
In large developments from one plasmodium on the inner side of 
the bark of old stumps, every variety of form is sometimes represented, 
from broad plasmodiocarps to globose and substipitate sporangia, and 
the colour may range from deep purple to grey. In gatherings where 
the colour is pure white, the outer layer of the sporangium -wall 
consists of crystalline deposits of lime without the intermixture _ of 
brown granules. The capillitium is subject to much variation according 
to the season of the year and other causes. In a gathering at Lyme 
Regis in the autumn, the capillitium was scanty, forming a net of 
rugged coarsely warted threads 2 to 4 /li diam., with a few scattered 
free threads ; in the following spring another growth on the same 
pieces of bark had sporangia of a similar shape and colour, but with 
a more abundant capillitium forming a freely branching slender net- 
work of minutely warted threads 1 to 1-5 /x diam., scarcely differing 
from that of P. rJqnrssa, the larger spores being the chief character 
which distinguished the gathering from that species. The specimens 
