TUBERCULOSIS. 



[Description of plates.] 



Plate XXXIV. Tuberculosis of the lungs. The upper figure represents a 

 large cheesy mass, surrounded by a capsule of connective tissue, the whole em- 

 bedded in healthy lung tissue. The lower figure illustrates in section a mass of 

 tubercles which have undei'gone cheesy degeneration, and some of which are 

 surrounded by dense connective tissue. 



Plate XXXV. Tuberculosis of the liver. A large portion of the lobe repre- 

 sented in the plate has undergone tuberculous changes. Numerous nodules are 

 shown in various stages of the disease, the majority of which, however, contain 

 the yellowish, partly cheesy, partly gritty areas characteristic of advanced 

 tuberculous degeneration. This large mass involves the surface of the liver, 

 and also extends into the liver substance. 



Plate XXXVI. A lymph gland from the region of the thorax behind or above 

 the esophagus, or gullet (posterior, or dorsal, mediastinum). The gland is 

 shown cut through and laid open. It is very much enlarged, and the yellowish 

 cheesy masses which represent tissue undergoing tuberculous changes are well 

 shown on the cut surface. 



Plate XXXVII. liepresents the omentum, or caul, of a tuberculous cow. The 

 preparation had been in alcohol for some time. The projecting masses are the 

 tubercles, whence the name "pearly disease" for that form of the malady in 

 which these tubercles are present. They are mainly restricted to the lining 

 membrane of the thorax and abdomen. 



Plate XXXVIII. Fig. 1. Lymphatic gland of the mesentery (the fold of mem- 

 brane to which the small intestines are attached) cut open. The gland is very 

 much enlarged. The yellowish portions represent tissue which has undergone 

 tuberculous changes. 



Fig. 2. Omentum, or caul, resting upon the paunch. The reddish nodules with 

 which the membrane is beset are tubercles, the product of the disease. Both 

 specimens are from the same animal, a Jersey cow. 



Plate XXXIX. Fig. 1. Tuberculosis of the sirloin and porterhouse cuts of 

 beef. The grapelike tuberculous growths are mainly restricted to the lining 

 membrane of the abdomen. 



Fig. 2. Tuberculosis of the pleura of cow, so-called " pearly disease." Notice 

 the grapelike clusters of tubercular nodules scattered over the lining membrane 

 of the chest (pleura). 



Plate XL. Tubei'culosis of a cow's udder which appeared uniformly swollen 

 and quite firm. Small cheesy foci and yellowish lines of tuberculous material 

 follow the course of the milk ducts. The mucous membrane of the milk cistern 

 (a) is ulcerated and covered with yellowish cheesy particles. The supramam- 

 mary lymphatic gland (&) is greatly enlarged and contains many miliary 

 tubercular foci. 



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