374 
MELANOSIS. 
the leftside are atrophied, including those of the lips; and running 
towards the tumours, in every direction, are a number of veins, of 
about the size of a small goose quill, which appear to terminate, in 
fact, in the tumours. The large tumour is more elastic than be- 
fore, and, upon inserting a lancet deeply into its substance, and 
withdrawing it, I found it to be covered with a coating of inky- 
looking matter, and immediately a small stream of the same colour 
issued from the opening, and ran down the tumour: this determined 
the case decidedly as being one of melanosis. The pulse was 60, 
and the respiration was difficult and laboured. Having thus satis- 
fied myself with respect to the nature of the disease, I at once, 
from numerous reasons, come to the conclusion that the case was a 
hopeless one, and told the owner to that effect, who consented 
to have her destroyed ; and, upon my expressing a desire to have 
the head and neck for dissection, he kindly promised it to me, so 
that I am enabled to furnish the reader with every particular re- 
specting this interesting case. On the 11th 1 received the head, 
and at once proceeded to make the necessary dissection. 
External appearance of the head, 8$c. when laid upon its right 
side . — Between the frontal suture, the curve of the inferior maxilla, 
and the supero-inferior part of the neck, three irregularly-formed 
tumours or masses are presented to view. The first and largest of 
the three is situated on the superior and outer part of the head, 
measuring between the root of the left ear and the outer canthus of 
the left eye eleven inches, and from the insertion of the abductor 
aurem muscle to the frontal suture thirteen inches : the inferior 
part of this tumour is much lobulated. Immediately below the 
above, and situated upon the curve of the maxilla, is the second 
tumour, which also is lobulated and irregularly circumscribed. 
Below this again is the third mass, which presents the same cha- 
racters, and occupies the angle formed by the junction of the neck 
with the head. 
Dissection. — On removing the skin, a dark transparent blue co- 
lour is exposed, which soon changed to almost black, after a little ex- 
posure to the air. The posterior part of the large tumour passes 
under the abductor aurem muscle — its supero-anterior part under the 
triangular cartilage of the ear, under the adductor aurem and 
temporo-auricularis internus muscles. On the removal of these, I 
exposed the temporal muscle, which muscle (in all cases in the 
horse) is covered with a glistening yellow tendinous substance, 
beneath which again the deposits were extended : they were not, 
however, limited to the cellular tissue in immediate contact with 
the tendinous portion, but the lower part of the muscle in imme- 
diate connexion with the cranium was filled with globular por- 
