f this important organ, is also a serious
matter. There is no reason to suppose that the localized disease interferes
with the general health in any other way than indirectly until internal
organs, such as the lungs, become involved.

A very small proportion of the cases may recover spontaneously, the tumors
being encysted or undergoing calcification. In most cases the disease
yields readily to proper treatment, and about 75 per cent of the affected
animals may be cured.

_Prevention._--The question as to how and where animals take this disease
is one concerning which we are still in the stage of conjecture, because so
far we possess very little information concerning the life history of the
actinomyces itself. The quite unanimous view of all observers is that
animals become infected from the feed. The fungus is lodged upon the plants
and in some way enters the tissues of the head, the lungs, and the
digestive tract, where it sets up its peculiar activity. It is likewise
generally believed that the fungus is, as it were, inoculated into the
affected part. This inoculation is performed by the sharp and pointed parts
of plants which penetrate the mucous membrane and carry the fungus with
them. The disease is therefore inoculable rather than contagious. The mere
presence of the diseased animal will not give rise to disease in healthy
animals unless the actinomyces grains pass directly from the diseased into
some wound or abrasion of the healthy or else drop upon the feed which is
consumed by the healthy. Not only are these views deducible from clinical
observation, but they have been proved by the positive inoculation of
calves and smaller animals with actinomyces. The danger therefore of the
presence of actinomyces for healthy animals is a limited one. Nevertheless
an animal affected with this disease should not be allowed to go at large
or run with other animals. If the fungus is being scattered by discharging
growths we certainly can not state at this stage of our knowledge that
other animals may not be infected by such distribution, and we must assume,
until more positive information is at hand, that this actually occurs.

It is, however, the opinion of the majority of authorities that when
actinomycosis appears among a large number of animals they all contract it
in the same way from the feed. Much speculation has therefore arisen
whether any particular plant or group of plants is the source of the
infection and whet