846 
ANALYSIS OP CONTINENTAL JOURNALS. 
— After what has been said, it is already evident that the 
disease described offers numerous analogies to the Tinea of 
children. The same essentially parasitic nature ; the same 
cupuliform aspect of the primary lesion ; the same composi- 
tion in the crusts ; and, lastly, a perfect resemblance between 
the constitutive elements of the microphyte that produces 
the two maladies. There is, therefore, nothing more re- 
quired to establish a complete identity between them than to 
prove that they are transmissible from one species to another ; 
that the Tinea of the child, for example, may be transmitted 
to the cat, and that the disease we produce in sowing on the 
skin of the cat the spores of Tinea derived from the infant 
clearly offers all the characters of the affection I have ob- 
served, and which I have described in this animal. This is 
■what I have undertaken to do. \ 
On the Tth February, 1866, M. Dron, at present chief 
surgeon in the Antiquaille Hospital, sent me some crusts 
taken from the head of a child affected with the dis- 
ease, and under his care. Some days afterwards I sowed them 
on the head of a cat, according to the procedure already 
indicated, and as a result I obtained a very fine Tinea, 
exactly similar to those produced in my previous experi- 
ments. There could be no doubt, then, as to this fact. 
The Tinea of the child is contagious for the cat, and this 
Tinea, transmitted directly from the child to the cat, offers 
the same characters as that transmitted directly from cat 
to cat. We might, therefore, from this conclude that the 
Tinea of the cat may also be transmitted to the child, and 
that, consequently, there is a complete identity between the 
two diseases. 
Etiology . — The essential cause of the malady in animals 
is contagion , or, to speak more exactly, the transfer of the 
spores of the Achorion from a diseased to a healthy animal. 
It cannot be conceived that there should be any other really 
efficient cause than this for such an essentially parasitic 
malady. But certain contingent circumstances have, never- 
theless, a real and very evident influence on its development. 
Among these contingent circumstances, the one whose ac- 
tion is best demonstrated is the age of the subjects. All the 
animals in which I have as yet observed the disease were 
young ; the cats, seven or eight in number, were only from 
six weeks to two months old ; the dog was about four 
months, and it was the oldest of my patients. 
The experiments referred to above confirm the influence 
which I have attributed to youth in the production of Tinea. 
I have twice attempted to transmit it to adult cats, but 
