102 
ft. E. SALMON. 
extremity. This fibro-cartilage may easily and more or less com¬ 
pletely become ossified ;. old horses are those which most com¬ 
monly present this condition, and draught horses are more subject 
to it than those used to the saddle. It may assume various forms. 
At times it occupies the entire extent of the cartilage, and others 
only at its base; sometimes the external surface is ossified, while 
the internal remains in its normal structure ; then amiin the ossi- 
fication exists only anteriorly while the posterior is cartilaginous, 
and it more rarely happens that the process consists in bony 
lamellae, which, starting from the base, spread towards various 
points of its circumference. 
These fibro-cartilages are generally more developed in the 
anterior than the posterior extremities. They also present, in 
one foot, this slight difference, that the internal stands a little 
higher than the external. 
Cartilaginous quittor is a serious affection characterized by 
the partial caries of one of the fibro-cartilages ; it is a partial 
gangrene whose character is to slowly spread into the cartilaginous 
structure upon which it starts. To be treated with success it 
requires a very regular attendance, and often an operation, which 
consists in the removal of the cartilage. Sometimes this oper- 
tion is indispensable, and its study is interesting, especially be¬ 
cause, though not as commonly performed as at the beginning of 
this century, it is one which requires a high degree of surgical 
skill for its success. 
(To be continued.) 
ON THE PRODUCTION OF IMMUNITY FROM CONTAGIOUS 
FEVERS BY INOCULATION WITH DILUTED VIRUS. 
By D. E. Salmon, D.V.M. 
(Continued from page'll.) 
% 
Interesting and important as the results I have detailed evi¬ 
dently are to the veterinarian and the agriculturist, they would 
be more or less out of place in this journal, were it not for the 
probability that the germs of the contagious fevers in men and 
