76 
TUMOUR ON THE OS HYOIDES. 
The nature of the lesions of the parts above alluded to 
is as follows : On the posterior border of the left supe¬ 
rior cornu of the os hyoides, there existed a large irregularly- 
shaped tumour, projecting in an inward and backward direc¬ 
tion. It was four inches in length from its attachment to 
the bone to its posterior extremity, and about the same dis¬ 
tance from the upper to the lower border. From the side to 
side it was about three inches. Its surface was somewhat 
uneven and moderately dense to the feel. I made a section 
through it, in a line from behind forwards, which was its 
greatest diameter, and found that it chiefly consisted of dense 
fibrinous tissue ; but in the centre there were numerous irre¬ 
gularly formed spaces, each containing thick inspissated pus, 
about the consistence of cheese. No other peculiarity, 
worthy of notice, could I detect, belonging especially to the 
tumour. 
I was next led to examine the bone to which the tumour 
was attached, and found the part which was embraced by the 
base of the tumour to be extensively diseased, evidently from 
an injury ; but how inflicted it would of course be difficult to 
say. The result was a throwing out of a quantity of osseous 
matter which had become formed into several nodular pro¬ 
jections on its inner surface and posterior border. 
About two inches and a half below this, the bone was a 
little enlarged and spongy in texture, as though it had at 
some time been injured and partly repaired, but had since 
become broken. Most likely this was done on removing it 
from the head after the mare was destroyed. 
The root of the tongue and base of the epiglottis, were 
considerably thickened, very dense in structure, and the 
upper surface much ulcerated. 
On making a section through the diseased mass and press¬ 
ing it, cheese-like matter exuded from numerous small open¬ 
ings. The hyo-epiglottidean muscle had nearly disappeared, 
and its place was occupied by a fibrinous deposition, which 
from its comparative unyielding nature, and the lost power 
of the above muscle to contract, the epiglottis was so far 
fixed as to partially close the glottis; the opening of which 
was further diminished by the pressure imparted to the left 
arytenoid cartilage by the tumour. 
Such is a brief outline of the morbid specimen. 
The most important point for consideration in this case 
is, the cause which gave rise, in the first instance, to the 
affection. To the practitioner of veterinary medicine this is 
of considerable interest, for he has often great difficulty in 
obtaining, from those in whose charge the patients are placed. 
