institution, partly because all available candidates seem reasonably
certain to be affected with lumpy-jaw, and partly because we are
unwilling to run further risks of having other hoofed animals inoculated
by them. Today we are anxiously wondering whether the jaw disease of the
prong-horn is destined to exterminate the species. Such a catastrophe is
much to be feared. This is probably one of the reasons why the antelope
is steadily disappearing, despite protection.

In 1906 we discovered the existence of actinomycosis among the black
mountain sheep of northern British Columbia. Two specimens out of six
were badly affected, the bones of the jaws being greatly enlarged, and
perforated by deep pits. The black sheep of the Stickine and Iskoot
regions are so seldom seen by white men, save when a sportsman kills his
allotment of three specimens, we really do not know anything about the
extent to which actinomycosis prevails in those herds, or how deadly are
its effects. One thing seems quite certain, from the appearance of the
diseased skulls found 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