352 
H, F. PALMER. 
or upon the ribs. Their peculiar location is due perhaps to 
their cause, which is often from an external injury. There are 
two forms, one being round or oval with well-defined limits, the 
other having no well-defined border but resembles an infiltra¬ 
tion into the surrounding tissue. These latter may arise from 
the development and growth of cartilage in an inflammatory 
exudate. 
The diagnosis of enchondromatous tumors is not generally 
a matter of difficulty. Their hard, slightly compressible feel¬ 
ing, their knobbed or irregular surface, their painless progress 
and usually their connection to cartilage or bone. The treat¬ 
ment consists in their removal as early as possible by excision, 
as their location especially on the sternum may cause great in¬ 
convenience to the animal’s movements. 
Osteoma .—These tumors, commonly described as exostoses, 
are masses of bone or outgrowth from different portions of the 
skeleton. In structure and chemical composition they agree 
with either the compact or spongy tissue of normal bone. In 
form, they are not uniform, being sometimes lobulated, some¬ 
times spherical, and at other times spinous or spiculated. They 
are of slow growth, and vary much in size. Except when the 
tumor attains considerable magnitude, little inconvenience is 
experienced by the animal, and when pain accompanies them it 
is due to their pressure on adjacent nerves, or its interference 
with the movement of tendons. Their extreme hardness and 
firm connection with bone are their chief characteristics. Being 
of slow growth, benign in their character, rarely attaining to 
any great magnitude, and having a tendency to become fixed, 
it seldom becomes necessary to remove them. If they do attain 
to such a size that their removal is necessary, they can be un¬ 
covered and detached with a saw. Even when they are pedun¬ 
culated and a portion of their stump is left, the base shows no 
disposition to grow. 
A myoma is a tumor consisting exclusively of muscular tissue. 
Ap hey are exceedingly rare, but may occur in two forms. One 
is allied in its histological structure to striated muscle, but hav- 
