312 : Case of Hydrocephalus. [APRIL, 
Hornets’ Combs, &c. 
Are likewise composed of rotten or touch wood in a hollow tree, 
which they clear out for the purpose. They are vice versd of wasps’ 
combs. Thus are the cells open, or have the mouth downwards. 
These cells are evidently single; for the pieces of which they are 
composed are sufficiently large to be distinguished by the naked eye; 
and the same piece may be distinguished on both sides of the same 
cell, the wood also being in different states of decay, the layers 
evidently showing that they are begun from the top, and carried 
downwards. 
—=_— 
As you sometimes give place in your Annals to some particular 
cases in surgery, at least as far as connected with natural history, I 
beg to inclose to you the following case of hydrocephalus or hydatids 
on the brain of a sheep :— 
About the middle of January, 1815, a young sheep was observed 
by the shepherd to be unwell, from its heavy and stupid appearance, 
such as standing still and bleating, and continually losing itself, or 
leaving the flock to which it belonged; the disease gradually, but 
continually, increasing, until it put on the certain symptoms of 
water gathering on the brain; that is, by the animal constantly in- 
clining to one side, until at last it describes a circle, which it gra~ 
dually decreases until it is unable to move more than the length of 
its body. From the first appearance of the disease until its fatal 
termination is generally from two to three months. ‘The present 
subject was taken from a large flock, and put into an enclosure close 
by my house; thus giving me an opportunity of seeing all its actions. 
One day, being frightened, it ran into a deep pond, in which it 
continued swimming in a rotatory manner until nearly exhausted 
before it could be got out. Iam at present unable to determine: 
as to the cause of the animal always turning to the affected side, 
whether it proceeds from a partial paralysis of the side affected (as 
they do not seem to feel the effect of the nerves crossing) or from 
the animal constantly leaning its head to the painful side. The 
hydatid seldom occupies more than one lobe of the brain, some- 
times posterior, sometimes anterior, is situated beneath the dura 
mater, and depresses the substance of the brain ; but there does not 
appear-to be any part of it absorbed. That part of the cranium 
immediately over the hydatid is so much reduced by absorption, 
that it js found to yield by pressure of the thumb and finger. In- 
deed, I have seen it completely absorbed, and the brain protruding 
itself between the cranium and scalp, the animal still living in that 
state. This case was operated upon about six weeks from its first. 
appearance, by turning back the scalp (having first ascertained the 
situation of the hydatid by pressure) and applying a triphine imme- 
diately, the bone was removed, The cyst protruded through the 
orifice, and was taken out by the fingers. A slight hemorrhage 
took place, which stopped by gentle pressure. The wound was. 
