DISEASE OF THE HEART OF A HORSE. 
5 
their under or ventricular surfaces having the tubercular condylo- 
matous feel, their upper surfaces and their attached parts being 
in appearance healthy. The TRICUSPID VALVES around their 
floating borders were at least four times their ordinary thickness, 
and from the inferior or ventricular surface of two of the valves — 
from one more than from the other — were growing excrescences of 
the same nature as those above described, of the magnitude of large 
peas : the superior (auricular) sides presenting, as in the former 
case, their natural aspects. The semilunar valves of the pulmonary 
artery bore no marks of disease. The endocardium exhibited the 
same red streaks and spots, signs of inflammation, as had been ob- 
served upon the reflex pericardium. 
28 th October . — I had had the mare’s hocks cut off before she 
was sent away, for a purpose unconnected with her case, when, on 
opening them to-day, to my surprise, I discovered them both to be 
in a high state of disease. Their cavities were full of deep or 
amber-coloured synovia, the fluid from one of them, actually col- 
lected, measuring full an ounce and a half*, and when poured 
into the glass was found loaded with flocculi of albumen, which, 
on standing, subsided to the bottom. The addition of nitric acid 
to the clear liquor produced a general and copious creamy white 
precipitate. The internal surface of the capsule of the joint pre- 
sented everywhere — save where the synovial membrane is re- 
flected upon the bones — a coating of one-fourth of an inch thick 
of lymph-like substance of the same amber colour as the synovial 
fluid ; and the sheaths of the tendons (of the hind limbs) as well as 
the pastern, coflin, and navicular joints — the latter in the most 
marked degree — presented the same amber tinge and incrassated 
condition of the synovia contained in them, with here and there 
some appearance of similar effusion. It is probable other joints 
may partake of this morbid action ; but this we have now no means 
of ascertaining. In the morbid condition in which the hock- 
joints were found we appear to have the key to the explanation of 
the “crouching gait” of the mare, mentioned in the symptomatology 
of her case, and which in the first, instance was erroneously attri- 
buted to some spinal affection. It is true that the spine was not 
examined after death ; it is equally true, however, that the stiffness 
or soreness created by motion, which was referred to the spine, 
was of a character to indicate stiffness in all her joints, and as 
such of her joints as were examined presented appearances of dis- 
ease, there seems every reason for believing that her complaints 
were not spinal at all, but arthritic . 
* In a state of health the hock joint may contain about three drachms of 
synovia — certainly not more than four. 
