HABITATS. 251 
sembled those of Sporidesmium polymorphum, under which name 
specimens were at first published,* but this determination was 
not satisfactory. The mycelium and erect threads are much too 
highly developed for a good species of Sporidesmium, although 
the name of Sporidesmium alternaria was afterwards adopted. 
In fresh specimens of this fungus, when seen in situ by a half- 
inch objective, the spores appear to be moniliform, but if so, all 
attempts to sce them so connected, when separated from the 
matrix, failed. On one occasion, a very immature condition was 
examined, containing simple beaded, hyaline bodies, attached 
to each other by a short neck. The same appearance of 
headed spores, when seen in situ, was recognized by a myco- 
logical friend, to whom specimens were submitted for con- 
firmation.t 
The last production which made its appearance on our wall- 
paper burst through the varnish as little black spheres, like 
grains of gunpowder. At first the varnish was elevated by 
pressure from beneath, then the film was broken, and the little 
blackish spheres appeared. These were, in the majority of cases, 
gregarious, but occasionally a few of the spheres appeared 
singly, or only two or three together. As the whole surface of 
the damp paper was covered by these different funyi, it was 
scarcely possible to regard any of them as isolated, or to declare 
that one was not connected with the mycelium of the others. 
The little spheres, when the paper was torn from the wall, were 
also growing from the under surface, flattened considerably by 
the pressure. The spherical bodies, or perithecia, were seated 
on a plentiful hyaline mycelium. The walls of the perithecia, 
rather more carbonaceous than membranaceous, are reticulated, 
reminding one of the conceptacles of Erysiphe, to which the 
perithecia bear considerable resemblance. The ostiolum is so 
* Cooke’s ‘‘Fungi Britannici Exsiccati,” No. 829, under the name of 
Sporidesmium polymorphum var. chartarum. 
+ This reminds one of Preuss’s Alternaria, figured in Sturm’s ‘‘ Flora ;” it 
has been suggested that the mould, as seen when examined under a power of 
320 diam., is very much like a Macrosporium. Again arises the question of the 
strings of spores attached end to end, 
