1884.] DISEASES OF CARNIVOROUS MAMMALS. 183 



If sections of a lung, which has been compressed by fluid in the 

 pleura for some considerable time, say six weeks, be examined by the 

 microscope, the following appearances will be noted : — 



The pleural covering is very thick, its surface being coated over 

 by a thick layer of organized lymph varying in thickness according 

 to the length of time the disease has existed. From the deeper 

 layers of the pleura there is an invasion of fibrous tissue into the 

 lung-substance, destroying the air-cells immediately subjacent to the 

 original serous covering. 



Beneath these disorganized air-cells, a considerable tract of airless 

 tissue exists in which the cell-walls are in apposition, and lie folded 

 together as neatly as a lady's fan. These cells, if inflated during life, 

 would again become functional. 



Approaching the main bronchus, curious changes may be seen ; 

 here and there whole tracts of the lung-tissue are in a state of com- 

 plete disorganization, others are seen with their opposite walls simply 

 in contact, whereas in many parts the air-cells are so dilated that 

 they present all the characters of emphysematous lung, so extreme 

 is the distension of the air-vesicles and so attenuated their walls. 

 Although the lung is apparently in a condition of extreme atelec- 

 tasis, yet in parts, paradoxical as it may seem, we have to do also 

 with a condition of emphysema and dilated bronchi. 



The Organs of Circulation. 



Few and far between are cases of diseases of the heart and blood- 

 vessels in carnivorous animals. Once only have I seen pericarditis, 

 and that was in a Coati. The disease was caused by the extension 

 of inflammation from old-standing double pleurisy. 



Valvular disease was seen in an Esquimaux Dog aged at least 

 twelve years. The endocardium was thickened and opaque, the 

 mitral and aortic valves presented vegetations on their free borders, 

 some of which had evidently been detached by the circulating current, 

 as three old infarctions in the liver bore indisputable testimony. 

 Atheroma was encountered twice, once in the aortic arch of a Dog ; 

 the remaining instance occurred in a Coati, in which the whole of the 

 descending aorta was affected, some of the patches being of con- 

 siderable size. 



The Alimentary Canal. 



Afi'ections of the digestive tract are uncommon. Typhoid ulcera- 

 tion of the ilium and colon has been twice noted in the course of 

 my dissections. The symptoms during life were such as to lead one 

 to suspect the nature of the malady, diarrhoea and hsemorrliage 

 from the bowel with similar cases turning up among other animals. 

 The two cases mentioned occurred in a Tiger and a Leopard, about 

 the same time as the cases referred to in my paper on Diseases of 

 Monkeys. 



Several Bears have died from enteritis, and in one a perirectal 

 abscess attained to a considerable size, then burst into the peritoneal 

 cavity, giving rise to intense and fatal inflammation. The abscess 

 was in all probability caused by a piece of bone passing through the 



