BENIGN TUMORS AND CYSTS. 
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develop slowly and do not adhere to the skin and adjoining tis¬ 
sues. Both kinds of tumors usually pursue a painless growth 
for a time, and the benign seldom causes pain unless from its 
bulk interfering with natural functions. Benign tumors have 
a feeble blood supply and they seldom contain any juice. 
Several theories have been advanced accounting for the ori¬ 
gin of tumors. The congenital, the nervous influence, sponta¬ 
neous and inflammatory theories all have their advocates- 
Whatever the growth may be, there are three conditions neces¬ 
sary for the development of a morbid growth—structural pecul¬ 
iarity, a specific irritant, and inflammation. 
Benign tumors are classified as follows : 
Fibroma or fibrous material. 
Epithelioma of skin. 
Osteoma of bone. 
Enchondroma of cartilage. 
Neuroma of nerves. 
Eipoma of adipose tissue. 
Adenoma of secreting glands. 
Myxoma of mucous tissue. 
Angioma of blood vessels. 
Myoma of muscle. 
Eymphoma of lymphatic tissue. 
Fibroma or fibrous tumor is usually found in parts contain¬ 
ing much fibrous tissue. It is a hard, rounded, painless tumor. 
Surface of tumor smooth or divided intp lobes, generally mov¬ 
able, and contained in a wall of areolar tissue. They vary in 
size from that of a grain of shot to a goose egg or even larger. 
They are made up of fibres of yellow elastic and white fibrous 
tissue which run in various and apparently confused directions. 
The compactness of these layers of fibre give the tumor a hard 
or soft nature. They have few blood vessels and are usually 
lodged in a sac and receive their nourishment from its walls. 
The favorite seat of these tumors is on the inferior surface of 
the abdomen, and also in the uterus, especially of the bitch. 
Diagnosis : 
