HYDATIDS IN THE BRAIN. 575 
that, when they were examined, vesicular ivorms were found in 
the substance of the brain. 
Curious Application of Percussion .—Wepfer speaks of an 
operation for the turnsick which he saw performed on some Swiss 
cattle. When this circular walk was observed, the beast was 
caught, and was struck with a hammer about the head and 
behind the horns; and the operator judged, by the shrinking of 
the animal, in what place there was a vacuum, and there he made 
an opening into the skull. This certainly does not coincide with 
the anatomy of the present day. We have seen that between 
the two plates of the cranium there is a continuous hollow from 
the nasal bone almost to the tip of the horn, and again poste¬ 
riorly to the very edge of the foramen magnum. We, too, should 
have suspected disease where the animal shrunk from the blow; 
but we should have predicated a collection of matter there, from 
inflammation of the lining membrane of the frontal sinus, and, 
by some adventitious texture, confined to a particular spot. I 
have spoken of this when describing the frontal sinuses, and 
inflammation of their lining membrane. Beneath the inner 
plate of the skull there is no vacuum as here described, but a 
watery cyst occupies the situation of the pulpy matter of the 
brain. How this was to produce the sensation demonstrated by 
percussion I am yet to learn. 
The Existence of the Hydatid may he ascertained in young 
Beasts by the Softening of the Skull at the Hoot of the Horn .— 
Wepfer very properly remarks, that the frontal sinuses are not 
fully developed in young beasts, and that the situation of the 
hydatid may frequently be detected in them, in the same manner 
as in sheep, by the softening of the cranial roof at some particular 
spot. This indeed would be decisive: but he speaks of an 
operation which he performed where he had not this guide, and 
depended on the pain caused by percussion; for he operated 
below the horn, and on the parietal bone, and through a mass of 
muscles,—and he operated successfully. 
Further Proofs of Hydatids in the Brain of Cattle.— The 
writer of a paper read before the Medical Society of Toulouse, 
describes a person who had operated on cattle twelve times for 
the extraction of the hydatid, and eight times out of the twelve 
with perfect success; and the same gentleman exhibited to the 
society two hydatids which he had extracted from the brain of a 
heifer eighteen months old. Our records, disgracefully scanty, 
confined in a manner to a periodical only seven years old, contain 
no history of turnsick in cattle; but I have seen, as I have 
already mentioned, one case of it: I have heard of others; and 
from the very frequent success which has attended prompt and 
