ANALYSIS OF CONTINENTAL JOURNALS. 
743 
pressure on the nail increases, its substance gets thinner and 
thinner, till perforation occurs ; and then a favus cup makes 
its appearance externally, but, according to Anderson, more 
or less deformed. 
It is important to notice that at first there is, at the point 
where the favus is about to form, only an increased secretion 
of epidermis ; and sometimes the under surface of the favus 
is coated by cuticle, which separates it from the compressed 
and attenuated derma. As it increases in size, and becomes 
more prominent, the epidermic covering is ruptured. Each 
favus crust is also enveloped in a capsule of amorphous struc- 
ture, within which is enclosed the true favus matter. 
The favus consists of the mycelium, the spores, and the 
receptacles of the Achorion, together with a finely granular 
amorphous layer, which forms the external coat of the favus, 
and is the representative of the amorphous “ stroma” which 
often accompanies the mycelium of fungi. In the favus 
another and distinct fungus can sometimes be found, namely, 
the Puccinia favi, which is easily recognised ; it has one 
extremity (the body) rounded, and composed of two cells of 
unequal size, a superior and an inferior ; the other extremity 
is prolonged into a jointed stem or trunk. 
When a little of the favus matter is broken up and exa- 
mined microscopically, after being acted upon by solution of 
potash, it is seen to consist of numerous little oval or rounded 
bodies, the sporules of the fungus having a diameter of about 
the 3 oVoth part of an inch. 
A number of cells united end to end form simple or jointed 
and branching tubes, developed from the sporules. Little 
granules or nuclei may be seen in the interior of the spores. 
The tubes vary in diameter, and hairs in the vicinity of the 
favus crusts are impregnated with the fungus. 
The disease had been communicated by inoculation from 
man to man, and from mice to cats, and thence to many, 
before Saint- Cyr’s observations were published (Aitken, 
Bazin, Draper, Fox, Anderson). 
Several years ago we had occasion to investigate the malady 
in a hutch of rabbits where it caused great havoc, and its 
transmission from one to another of these animals was clearly 
traced. The cat is a frequent subject of the disease, and it 
would even appear that it manifests itself in an epizootic 
form in that animal. Our c History of Animal Plagues 5 con- 
tains notices of what would appear to be outbreaks of this 
malady, and especially the extraordinary one that occurred 
in 1796. 
We have ventured to offer these preliminary remarks 
