536 
ANALYSIS OF CONTINENTAL JOURNALS. 
outlets of mucous cysts, which we had by a negligent care¬ 
lessness attributed to the friction of the bridle and headstall. 
Extirpation being the shortest and the surest means to 
effect the cure, was at once resorted to; the patient being 
cast and secured, the incisions were made parallel with the 
fistulas, so as to enable the dissection to be made more com¬ 
pletely. The cysts being successfully removed, the wounds 
were closed with sutures, and in about twelve days the cures 
were.completed. 
These two sacs had exactly the same arrangement adhering 
to the os temporalis, a little below the zygomatic apophysis, 
at the union of the petrous portion of the temporal bone, and 
they were easily detached; nothing particularly remarkable 
was observed at the bottom of the sac, everything perfectly 
agreeing with the idea we had at first formed of the nature of 
the disease. But since we know that they were of the same 
nature and origin as the last case, we ask ourselves this ques¬ 
tion, What had become of the tooth? did the dental ovulum 
abort, or did the tooth remain attached to the bone ? This 
last supposition does not appear impossible. From the obser¬ 
vations communicated by M. Derache, the fact is that dentary 
tumour persists in the manner of hyperostosis after the de¬ 
struction of the mucous membrane. From which it results 
that after the extirpation of the cystiform tumour, cicatri¬ 
sation might take place, and the tooth remain without any 
abnormal secretion or fistula betraying its presence. 
M. Macorps is not of the same opinion, for this practitioner 
informs us that on fourteen horses he has operated twice, in 
one case three months intervening, and at each time he 
extracted a tooth; and further, that the cysts and the fistula 
have persisted, notwithstanding the repeated puncture of the 
tumour, and the injection of iodine, the employment of the 
red hot iron and setons, that after the use of these means 
the tumour reappeared, from which it is presumable that a 
third tooth was forming. 
The author afterwards operated in the same way on two 
horses, who had each a fistula on the left temporal region, 
and a third case in which a peculiarity presented itself; a 
horse eight to nine years old had been affected for several 
years with fistula in the left temporal region, presenting 
exactly the same characters as those we have before described, 
only the discharge from it was turbid, and of a greyish 
colour, and emitted the odour of caries; the probe denoted a 
rough hard surface. From this fistula we extracted, to our 
great astonishment, a hard round substance, the size of a 
filbert, of a bony appearance, and uneven surface, resembling 
