POLYMORPHIC FUNGI. : 405 
within the pellicle, just as had been observed in a previous culti- 
vation, precisely similar revolving movements being also mani- 
fested.” Here we have another example of a Mucor developed 
from a Penicillium, and one observation strengthens and confirms 
the other 
Before entering upon the details of the second apparent poly- 
morphism, it may be as well to give some particulars of the cir- 
cumstances under which the fungi appeared. It was our fortune — 
good fortune as far as this investigation is concerned — to have a 
portion of wall in our dwelling persistently damp for some months ; 
it was close to a cistern that became leaky. The wall was papered 
with ‘“ marbled” paper, and varnished. At first there was for 
some time — perhaps months — nothing worthy. of observation 
except a damp wall; decidedly damp, discolored, 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 elevation. They projected from the paper about a quar- 
ter of an inch. In the course of a few weeks the color of the 
tufts became less pure, tinged with an ochraceous hue, and resem- 
bling wool rather than cotton, less beautiful to the eye or 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 pinheads, or grains of gun- 
powder, were found scattered about the damp spots. All this 
mouldy forest was more than six months under constant observa- 
tion, and, during this period, was held sacred from the disturbing 
influences of the housemaid’s broom, being consigned to the mas- 
ter’s care with little compunction, but occasionally it became the 
subject of remarks not altogether flattering either to the wall or 
the moulds, or the master who was protector and patron of such a 
wretched mess. 
Curiosity prompted us from the first to submit the mouldy deni- 
zens of the wall to the microscope, and this curiosity was in- 
creased 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 
