PSEUDO-SCLEROTIA OF LENTINUS SIMILIS, &C. 
7 
following stains have been tried without effect : Congo red, 
eosin, Belafeld’s hæmatoxylin, methyl green, picric aniline 
blue, safranin, sudan III., methylene blue. 
Fischer found that in the sclerotium known as Pachyma 
cocos three forms of hyphæ were present. The first were of 
normal shape, 2-4 ^ diameter, but with a strongly thickened 
wall, so thick that the lumen was reduced to a minimum. 
These swelled slightly in caustic potash, and were not stained 
by safranin, methyl green, methylene blue, or Congo red. 
The second form, which constituted the chief constituent 
of the sclerotium, consisted of irregular coralloid bodies, which 
were determined by Fischer to be hyphæ modified by the 
deposition of reserve substances in their walls. These 
dissolved in caustic potash, with the exception of the outer 
layer of the hypha. These bodies were not stained by chlor- 
zinc -iodine nor iodine. They stained strongly with methylene 
blue, or Congo red, or methyl violet, but not with methyl 
green or safranin. 
The third constituent of Pachyma cocos consisted of larger 
oval refractive bodies, in which an evident lamination could 
be observed. These gave the same reactions as the second. 
Judged by their shape the hyphæ in the pseudo -sc lerotia 
of Lentinus similis correspond with the first two constituents 
of Pachyma cocos, but it will be seen that the reactions of 
the hyphæ of Lmtinus similis correspond with those of the 
normally-shaped hyphæ of Pachyma cocos, not with the 
abnormally thickened constituents of the latter. I have not 
been able to consult Cohn and Schroeter’s paper on Lentinus 
Woermanni, but, according to Bommer (1), the thickened 
elements of its sclerotium dissolve in caustic potash. 
The red external colour of the pseudo -sclerotium is due to 
an amorphous deposit in the lumina of the fibres, &c., which 
open to the exterior. It is apparently homologous with the 
deposit frequently found, usually in black sheets, in wood 
attacked by various species of Pyrenomycetæ. von Schrenck 
(12) describes a brown substance found limiting the decayed 
wood of lilac attacked by Polyporus versicolor, which he states 
results from the drying up of a yellow-brown liquid which 
fills the cells, and probably consists of decomposition products 
