236 BUREAU OF ANIMAL INDUSTKY. 



have sometimes been embedded in the cardiac walls. Fibrinous coagula 

 ^n(\.j)oly2)Ous concretions may be found in the cavities of the heart. The 

 former consist of coagulated fibrin, separated from the mass of blood, 

 of a whitish or j^ellowish white color, translucent, of a jelly-like con- 

 sistence, and having a nucleus in the center. They may slightly 

 adhere to the surface of the cavit}^, from which they can easily be 

 separated without altering the structure of the endocardium. They 

 probably result from an excess of coagulabilit}^ of fibrin, which is 

 produced by an organization of the lymph during exudation. The}'- are 

 usually found in the right auricle and ventricle. 



Polypous concretions are firmer than the preceding, more opaque, 

 of a fibrous texture, and may be composed of successive layers. In 

 some instances they are exceedingly minute, while in others they 

 almost fill one or more of the cavities. Their color is usuall}' white, 

 but occasionally red from the presence of blood. They firm!}- adhere 

 to the endocardium, and when detached from it give it a torn appear- 

 ance. Occasionally, a vascular communication seems to exist between 

 them and the substance of the heart. They may be the result of 

 fibrinous exudation from inflammation of the inner surface of the heart 

 or the coagulation of a portion of the blood which afterwards contracts 

 adhesion with the heart. These concretions prove a source of great 

 inconvenience and often danger, no matter how formed. The}^ cause 

 a diminution in the cavity in which they are found, thus narrowing 

 the orifice through which the blood passes, or preventing a proper 

 coaptation of the valves, which may produce most serious valvular 

 disease. 



Symptoms. — These are frequently uncertain; they may, however, 

 be suspected when the action of the heart suddenly becomes embar- 

 rassed with irregular and confused pulsations, great difliculty of 

 breathing, and the usual signs dependent upon the imperfect artcriali- 

 zation of the blood. 



Treatment. — Stimulants, whisk}^, or carbonate of ammonia may be 

 of service. 



PALPITATION OF THE HEART. 



This is a tumultuous and usually irregular beating of the heart. It 

 may be due to a variety of causes, both functional and organic. It 

 may occur as a result of indigestion, fright, increased nervousness, 

 sudden excitement, excessive speeding, etc. (See "Thumps," pp. 

 140, 205.) 



Symptoms. — The heart may act with such violence that each beat 

 may jar the whole body of the animal; very commonly it may be 

 heard at a short distance away from the animal. It can usuall}^ be 

 traced very readily to the exciting cause, which we may be able to 

 avoid or overcome in the futui'e and thereby obviate subsequent 

 attacks. Rest, a mild stimulant, or a dose or two of tincture of digi- 



