by the writer in the taxidermic laboratory of
Frederick Sauter, in New York. The enormous swelling of the diseased jaw
bones clearly indicates a disease that in some cases affects its victim
throughout many months. Such a condition as we found in those sheep
could not have been reached in a few days after the disease became
apparent. Now, in our antelopes, the collapse and death of the victim
usually occurred in about 10 days from the time that the first swelling
was observed: which means a very virulent disease, and rapid progress at
the climax. The jaw of one of our antelopes, which was figured in Dr.
Blair's paper in the Eleventh Annual Report of the New York Zoological
Society (1906) shows only a very slight lesion, in comparison with those
of the mountain sheep.

The conclusion is that among the sheep, this disease does not carry off
its victims in any short period like 10 days. The animal must survive
for some months after it becomes apparent. At least two parties of
American sportsmen have shot rams afflicted with this disease, but I
have no reports of any sheep having been found dead from this cause.

This disease is well known among domestic cattle, but so far as we are
aware it never before has been found among wild animals. The black sheep
herds wherein it was found in British Columbia are absolutely isolated
from domestic cattle and all their influences, and therefore it seems
quite certain that the disease developed among the sheep
spontaneously,--a remarkable episode, to say the least. Whether it will
exterminate the black mountain sheep species, and in time spread to the
white sheep of the northwest, is of course a matter of conjecture; but
there is nothing in the world to prevent a calamity of that kind. The
white sheep of Yukon Territory range southward until in the Sheslay
Mountains they touch the sphere of influence of the black sheep, where
the disease could easily be transmitted. It would be a good thing if
there existed between the two species a sheepless zone about 200 miles
wide.

I greatly fear that actinomycosis is destined to play an important part
in the final extinction that seems to be the impending fate of the
beautiful and valuable prong-horned antelope. In view of our hard
experiences, extending through ten years (1902-1912), I think this fear
is justified. All persons who live in country still inhabited by
antelope are urged to watch for this disease. If any antelopes are found
dead,