243 FUNGI. 
universal wherever decaying vegetable matter is found, and 
that under some conditions animal substances, especially of 
vegetable feeders, such as insects, furnish a pabulum for their 
development. 
A very curious and interesting inquiry presents itself to our 
minds, which is intimately related to this subject of the heitats 
of fungi. It shapes itself into a sort of “puzzle for the curious,’ 
but at the same time one not unprofitable to think about. How 
is the occurrence of new and before unknown forms to be 
accounted for in a case like the following? * 
It was our fortune—good fortune as far as this investigation 
was concerned—to have a portion of wall in our dwelling per- 
sistently damp for some months. It was close to a cistern 
which had become leaky. The wall was papered with “marbled” 
paper, and varnished. At first there was for some time nothing 
worthy of observation, except a damp wall—decidedly damp, 
discoloured, but not by any means mouldy. At length, and 
rather suddenly, patches of mould, sometimes two or three 
inches in diameter, made their appearance. These were at first 
of a snowy whiteness, cottony and dense, just like large tufts of 
cotton wool, of considerable expansion, but of miniature eleva- 
tion. They projected from the paper scarcely a quarter of an 
inch. In the course of a few weeks the colour of the tufts 
became less pure, tinged with an ochraceous hue, and resembling 
wool rather than cotton, less beautiful to the naked eye, or under 
a lens, and more entangled. Soon after this darker patches 
made their appearance, smaller, dark olive, and mixed with, or 
close to, the woolly tufts; and ultimately similar spots of a 
dendritic character either succeeded the olive patches, or were 
independently formed. Finally, little black balls, like small 
pin heads, or. grains of gunpowder, were found scattered about 
the damp spots. All this mouldy forest was more than six 
months under constant’ observation, and during that period was 
held sacred from the disturbing influences of the housemaid’s 
broom and duster. 
Curiosity prompted us from the first to submit the mouldy 
® “Popular Sci:nce Review,” vol. x. (1871), p. 25. 
