DISEASES OF THE HEART IN DOMESTIC ANIMALS. 
413 
fatty tissue, and the fatty degeneration of the muscle of the 
heart (steatosis cardis). 
The excessive production of fatty tissue consists in the accu¬ 
mulation of an unusual amount of fat on the surface of the heart. 
In form of fatty lobes it envelopes the whole bulk of muscle and 
causes the heart to appear enlarged. Beneath the separated fat, 
which is less consistent than the normal fat, oily and of a dirty 
yellow color, the muscle of the heart is found partly normal, 
partly atrophied, pale and fallow, also fatty degenerated. Such 
conditions are frequently found in obese dogs. 
The second form represents the fatty degeneration of the muscle 
of the heart (steatosis cordis) which is frequently met with in horses, 
swine and sheep. The excessive growth of fat gradually lodges 
between the muscular fibres and is generally quite obvious be¬ 
tween the primitive bundles. Occasionally, however, the degen¬ 
eration is more or less extended, or is found in small, acute cir¬ 
cumscribed spots which appear pale yellow, unctuous and fragile. 
(Roll). Beneath the fatty tissue the normal muscular substance 
gradually becomes less, and often decreases to one-third its nor¬ 
mal thickness; at the same time the muscle of the heart is tawny 
and yellow, highly discolored, relaxed and easily torn. 
Another form is the degeneration and new formation of the 
cellular tissue, as thickening of the interior lining of the heart 5 
also on the valves warty protuberances and vegetations; sinewy 
callosities on different parts of the heart. Development of calca¬ 
reous concretions is often connected with these new formations'of 
cellular tissues by which the chamber walls are then partially 
broken through. Some observers also mention fibrine on the 
walls" of the heart on the valves. Cysts in the muscle of the 
heart are very rare; at least, in literature they are very seldom 
recorded. 
Fibrinous coagulations, on the contrary, are not so rare as is 
generally supposed. They are found in the cavity of the heart 
and on the valves, attached to parts which have become softened 
by inflammation; also as prominent round masses in the cavity 
of the heart. These consist of yellow solid, dry, very fragile 
fibrine. In its dipper position it encloses sometimes altered red 
