CONTRIBUTIONS TO VETERINARY PATHOLOGY. 255 
were, however, some eight or ten large holes through the par- 
tition to ventilate the roost, which afforded a ready means of 
exit for the unpleasant visitors in question. In this case the 
fowls were removed, and the horses soon ceased, as in the other 
case, to exhibit any signs of itching, without the aid of treatment. 
Several similar cases have since come under my notice, yet, 
in every instance, the removal of the hen-roost has been fol- 
lowed by a disappearance of the affection. 
I remain, your humble servant. 
To Mr. Percivall. 
CONTRIBUTIONS TO VETERINARY PATHOLOGY. 
By Wm. Smith, M.R.C.V.S., Veterinary Establishment, Norwich. 
[Fifth Contribution.] 
Encysted Serous Abscess, with Cartilago-osseous Sac — Lacera- 
tion of the Jugular Vein and Vena Cava ; with Remarks, fyc. 
On the 27th of March last 1 visited a cart mare, for the 
purpose of examining a swelling of some size on the left thigh, 
the consequence of a kick. The tumour is situate a little below 
the stifle joint, on the outside, extending in a line towards the 
hock ; being about ten inches in length, and in breadth some- 
thing like five inches. It is circumscribed, soft, elastic, and 
fluctuating to the touch, occasioning no perceptible pain on 
pressure, and little lameness. 
The injury which produced this tumour occurred some two or 
three months since. Fomentations were used at first, and af- 
terwards slight stimulants were resorted to. In the interval 
between the accident and the period at which 1 saw her, as she 
was not very lame, she was soon put to her work again, and 
continued at it until my visit. Exercise was producing a tem- 
porary diminution in its size, rest having a contrary effect. 
Upon examining the tumour, I detected the presence of fluid, 
and felt also a hard and apparently cartilaginous plate imme- 
diately beneath the skin, of the size of the palm of the hand, 
and of an oval form. I was solicited to put a seton through the 
abscess; but, as it presented some unusual features, I deter- 
mined upon exposing its interior to view by means of the 
scalpel. For this purpose I made an incision, first, through the 
skin, directly over this cartilaginous body, and then through it, 
making the opening large enough to admit two fingers. From 
