196 
ENDOSPOREiE. 
[PERIOn^NA. 
KEY TO THE SPECIES OP FERICUJENA. 
A, Sporangium-wall stout, brown, black or grey, inner layer 
smooth. 
Capillitium spinose, abundant. 1, P. chryaosperma 
Capillitium minutely warted, abundant ; spores 10 to 
11 /A diam. 2, P. depressa 
Capillitium minutely warted or nearly smooth, 
scanty; spoi'es 12 to 14 yu, diam, 3. P. populina 
B. Sporangium-wall yellow or pale umber, inner layer papillose. 
4. P. variabilis 
1. P. chrysosperma Lister. Plasmodium pale brown, in rotten 
bark. Sporangia subglobose, sessile, or shortly stalked, often 
forming horse-shoe or ring-shaped plasmodiocarps, scattered, 
0*4 to 1 mm. diam., chestnut or red-brown, dehiscing irregularly; 
sporangium-wall of two layers, the outer composed of bx*own 
granular matter, which either forms a complete crust, or is more 
or less obsolete ; the inner layer subcartilaginous, yellowish-olive, 
translucent. Stalk, when present, stout, black. Oapilhtium 
abundant, forming a loose network of sparingly branched yellow 
threads 2 to 4 /x diam., irregularly constricted, spinose, spines 
1 to 6 /u- long, subulate, curved, scattered. Spores citron-yellow 
in mass, minutely warted, 9 to 10 /a diam., rarely 7 to 8 /a. — 
Ophiotheca chrysosperma Currey, in Quart. Micr. Journ.,ii., p. 240 
(1854). Trichia circumscissa Wallr., El. Cryp. Ger., p. 378 (1833). 
Cornuvia circumscissa E,ost., Mon., p. 290 ; Cooke, Myx. Brit., 
p. 76. Ophiotheca circumscissa Mass., Mon., p. 131. Ophiotheca 
Wrightii Berk. & Curt., in Journ Linn. Soc, x., p. 349 ; Mass., 
Mon., p. 132. Cornuvia Wrightii Rost., Mon., App., p. 36 ; 
Macbride, in Bull. Nat. Hist. Iowa, ii., p. 122. 
Plate LXXI., A. — a. sporangia, stalked and sessile, x 20 ; b. capillitium 
from difEerent sporangia growing on the same piece of walnut bark, and 
spore, X 600 (England). 
It would appear that Rostafinski excluded this species, which he 
named Cornuvia circumscissa^ from the genus Perichoina, because he 
defined that genus as having oapilhtium without characteristic 
thickenings ; but in P. populina, to which this definition most nearly 
applies, the capillitium is usually closely warted and nptclied, rarely 
smooth, while in some gatherings the threads are beset with scattered 
sharp spines in addition to crowded spinules. In P. depressa and 
P. vermicularis the capillitium is never smooth, though the thickenings 
may be reduced to minute warts ; the character given by Rostafinski 
is therefore inapplicable, and in every feature except the large 
development of spines on the threads, P. chrysosperma is closely allied 
to the other members of the group. In a gathering of this species at 
Lyme Regis, two of the sporangia examined have smooth threads with 
a few minute spines distantly scattered, in others the spines are of the 
usual form, loosely set, and about 2-6 /it long; but in the greater number 
of sporangia the spines measure 5 to 6-6 fi in length. The characters 
