EXCISION OF A LARGE MELANOTIC TUMOUR IN A MARE. 51 
haunches. This rendered the operation more easy, and gave more 
freedom to the manipulations of the operator. I caused the tail to 
be turned over on the croup, and she was kept in that position 
during the whole of the operation. I surrounded the apparent 
portion of the melanotic mass by an incision through the sound 
skin, and taking care to adapt it to the margin of the anus. The 
concealed portion of the mass extending a little below the incision, 
I dissected to the very limits of the tumour in the whole circum- 
ference of the mass. I then seized the tumour towards the middle 
part of it with a strong double crotchet. In pulling strongly with 
the crotchet from the left to the right, and from before backwards, 
I was able to execute a slight movement backward and to the right 
of the mass, which I dissected as deeply as I could on the left, below 
the anus and the rectum, which was fortunately separated from the 
mass by a very loose cellular tissue. 
After having grasped the tumour anew by means of the crotchet, 
I brought it down as low as possible, and continued the dissection 
in that region. The cellular tissue, which was united to the sub- 
sacral surface, was serrated, and hard, and cracked under the 
bistoury. 
I was often obliged to divide the tumour in points that were in 
immediate contact with the bone. I suspended for a moment the 
attempt to excise the melanotic isolated parts with a cutting instru- 
ment in order to continue the dissection more deeply, for I came, 
as on the left side, to a chasm of considerable depth. By mani- 
pulations analagous to the preceding, I dissected away the mela- 
notic mass from its right and inferior portion. 
This first part of the operation being terminated, and we may 
almost say without effusion of blood, for we had only two small 
arteries to tie, I endeavoured to determine by the touch what 
was the exact depth to which the tumour penetrated, by intro- 
ducing my fingers into the incisions. I assured myself that the 
mass extended into the basin seven or eight centimetres beyond 
the bottom of the incisions already made. In order to obtain 
a complete excision of the tumour, I applied the airigne (a sharp 
hook) to the inferior part of the mass, which I thus raised as much 
as possible, in order to detach it completely from the rectum, and 
commenced dissecting towards that region. I also had to avoid 
the peritoneum. While acting thus, I, from time to time, made 
incisions from the left to the right, always with a view of being 
able to separate the tumour from the rectum, which, as I have 
already stated, had been pushed a little to the left by the tumour. 
I shall here repeat, that the disposition of the cellular tissue which 
united the tumour to the intestine, and which tissue was very flabby, 
did not permit me to reach the anterior extremity of the tumour. 
