112 NEW YORK ZOOLOGICAL SOCIETY. . 



One of the most interesting of the rare diseases was a case 

 of aneurism of the Jieart, which occurred in a Newfoundland 

 caribou. The case is of such interest that I shall abstract quite 

 extensively from the protocol and microscopical examination. 



The animal had been ailing for some time, suffering from 

 occasional attacks of diarrhoea and finally dying apparently from 

 malnutrition. At the post-mortem the following cardiac condi- 

 tion was found: 



"The heart as a whole is large and well formed. The epicar- 

 dium shows no areas of thickening or of injection, except over 

 the posterior portion of the apex, where a thick fibroid scar ex- 

 tends forward to a little beyond the anterior border. The entire 

 scar measures 6 cm. vertically, and 4 cm. horizontally. The 

 scar involves the left ventricle near its apex chiefly. On incising 

 this tissue it is found to contain large blood clefts, many lymph 

 spaces, and to be made up mostly of loosely arranged connective 

 tissue, the external layers of which are much more compact. 

 The average thickness of the scar which extends through the 

 entire wall of the ventricle is 5 cm., and it has evidently bulged 

 out from the regular contour of the heart to a considerable de- 

 gree when under blood pressure. 



"The myocardium, as a whole, is pale and abnormally soft. 

 The auricles show general thickening of the endocardium, es- 

 pecially of the left auricle, and the mitral valves show a moderate 

 degree of relative insufifiiciency. All the cavities of the heart 

 contain a small amount of mixed clot. 



"The arch of the aorta shows a slight degree of atheroma, which 

 is not continued into the coronary trunks, the intima of which 

 appears normal, though the vessels are of unusually wide calibre. 

 The lower one-third of the left coronary artery which should 

 supply the area involved by the scar is completely occluded, and 

 from this point on is marked as a simple fibrous cord extending 

 down, and finally blending with the fibrous wall of the aneurism. 



"The muscle cells in sections remote from the gross lesion 

 show a highly granular cytoplasm, and a few contain oil globules, 

 some of large size. The fatty degeneration is much more pro- 

 nounced in sections taken from near the aneurismal wall. There 

 is a marked infiltration w-ith small round cells in the immediate 

 neighborhood of the fibroid area, the muscle fibres becoming 

 more and more infrequent and more highly degenerated as the 

 aneurism is approached, where muscular tissue is completely re- 

 placed by adult and embr3^onic connective tissue, the cells of 

 which show a still active state of hyperplasia. The blood-vessels 



