MELANOSIS. 
o 
O 
mass, resembling the portion I have sent you. Black matter of the same 
character was also adhering to the ribs—both the true and false. The 
other lung and the heart were healthy. A number of black tubercles existed 
in the mesentery, but the liver, spleen, and all the other abdominal organs 
were healthy. 
Believe me, gentlemen, 
Your obedient servant, 
Charles M. Blake, M.R.C.V.S. 
The spleen sent by Mr. Hooper was simply examined by 
me with reference to its form, weight, and general appearance, 
as far as the unaided eye could observe. In colour, it was 
a dark gray, and much darker in some parts than in others. 
Its surface was irregularly nodulated, the nodules varying 
from the size of a walnut to that of a maids fist, the extreme 
summits of these enlargements being much darker than any 
other part of the organ. Its weight was forty-seven pounds, 
which, although very large, it is exceeded by one, the cast of 
which is in the College Museum. I have no doubt but the 
one sent by Mr. Jones was also heavier, but unfortunately it 
was not weighed. 
In making a section through the centre of the spleen, the 
cut surfaces presented a somewhat varied aspect. In those 
parts unaffected by the presence of pigment, or but very 
slightly involved, it was of a dark reddish-brown colour, 
slightly striated by the white edges of the cut trabiculae. It 
was also thirdy speckled with very small Malpighian bodies. 
Where the section passed through the centre of the enlarge¬ 
ments, it presented a blackish slate colour, crossed here and 
there with a few fine white lines. Its capsule, and peritoneal 
coverings, varied in thickness. In no part were they thicker 
than natural, but where they covered the upper portion of the 
tumour they were unusually thin. This brief description 
equally applies to both spleens, for the morbid alteration 
which had taken place in the structure of the one sent by 
Mr. Jones, appeared to be identical with that observed in 
Mr. Hooper’s case. 
With reference to Mr. Blake’s case I cannot think, nor 
do I suppose he thought, that the melanotic tumours 
which he mentions as being situated under the tail of the 
animal, were of themselves sufficient for him to conclude 
that others existed to any great extent in the lungs, or that 
her illness depended upon their presence ; he therefore treated 
the mare in accordance with the symptoms he observed. 
Had he been able to diagnose the case, which I believe could 
not have been done, he would, as a matter of course, have 
ordered the mare to be destroyed in the first instance. 
