HABITATS. 249 
denizens of the wall to the microscope, and this curiosity was 
increased week by week, on finding that none of the forms 
found vegetating on nearly two square yards of damp wall 
could be recognized as agreeing specifically with any described 
moulds with which we were acquainted. Here was a problem 
to be solved under the most favourable conditions, a forest of 
mould indoors, within a few yards of the fireside, growing quite 
naturally, and all strangers. Whence could these new forms 
proceed ? 
The cottony tufts of white mould, which were the first to 
appear, had an abundant mycelium, but the erect threads which 
sprang from this were for a long time sterile, and closely inter- 
laced. At length fertile threads were developed in tufts, mixed 
with the sterile threads. These fruit-beavers were shorter and 
stouter, more sparingly branched, but beset throughout nearly 
their whole length with short patent, alternate branchlets. 
These latter were broadest towards the apex, so as to be almost 
clavate, and the extremity was beset with two or three short 
spicules. Each spicule was normally snrmounied by an obovate 
spore. The presence of fertile threads imparted the ochraceous 
tint above alluded to. This tint was slight, and perhaps would 
not have been noticed, but from the close proximity of the snow- 
white tufts of barren threads. The fertile flocci were decumbent, 
probably from the weight of the spores, and the tufts were a 
littlo elevated above the surface of the matrix. This mould 
belonged clearly to the Ducedines, but it hardly accorded weil 
with any known genus, although most intimately related 
to Rhinotrichum, in which it was placed as Lhinotrichum 
lanosum.* 
The white mould having become established for a week or 
two, small blackish spots made their appearance on the paper, 
sometimes amongst thin patches of the mould, and sometimes 
outside them. These spots, at first cloudy and indefinite, varied 
in size, but were usually less than a quarter of an inch in 
diameter. The varnish of the paper was a‘terwards pushed off 
* Specimens of this mould were distributed in Cooke’s ‘Fungi Britannici 
Exsiccati,” No. 356, under the name of Clinotrichum lanosum. 
12 
