TUBERCULOSIS. 413 



by a short pedicle or neck and may be moved slightly to and fro. 

 Large masses are frequently formed by a coalescence of many tuber- 

 cles and the secondary formation of the same. These may be found 

 on the lungs, the ribs, and the diaphragm. These tubercles likewise 

 undergo degenerative changes. The center partly softens and partly 

 calcifies into a grayish mortarlike mass, and is gritty. Associated 

 with the formation of tubercles on the pleura, those glands situated 

 back of the center of the lungs between the two main lobes (posterior 

 mediastinal) become greatly enlarged and the center cheesy. (PI. 

 XXXVI, fig. 1.) They may compress the esophagus and interfere 

 with swallowing. The size attained by these tumors and new 

 growths is well illustrated by the fact that, taken together, they not 

 infrequently weigh from 60 to 80 pounds. The bronchial glands, 

 which in the healthy state are not so large as horse-chestnuts, have 

 been found to attain a weight of more than 10 pounds. 



In the abdominal cavity tubercles may be found, both in the 

 organs and on the serous membranes covering them. They are 

 situated preferably on the omentum, or caul (see PI. XXXVI, fig. 2), 

 the diaphragm, and the walls of the abdomen. In the liver large 

 and small tubercular masses are occasionally encountered. (See 

 PL XXXV.) The mesenteric glands are occasionally enlarged and 

 tuberculous; likewise the glands near the liver. Tubercles may also 

 develop in the spleen, the kidneys, the uterus and ovaries, and the 

 testicles. 



Tubercular affection of the intestines seems to be quite rare, 

 although ulcers of the large intestines have been observed. Nodules 

 may also form under the serous covering of the intestines. 



The brain and spinal cord are occasionally found tuberculous. Of 

 40 cases, Semmer found tuberculosis of the brain in 4. It is not 

 improbable that, owing to the infrequency of exposing the brain and 

 spinal cord, tuberculosis may have escaped the attention of patholo- 

 gists, and it may be that it is not so uncommon as is generally, sup- 

 posed. The tubercles occur on the membranes of the brain as well as 

 in the substance of the brain itself. They project into the ventricles 

 as masses, varying in size from a pinhead to a hen's egg. They 

 finally lead to various inflammatory changes. Johne has observed 

 numerous small tubercles on the membranes of the spinal cord. 



Very rarely tuberculous lesions have been observed in the bones 

 and muscles of the hodj. Not so rare, however, is the affection of the 

 lymphatic glands embedded in the muscular tissue, and those which 

 can be felt beneath the skin. These are situated at the joints, under 

 the jaw, and along the neck. 



Of late tubercular disease of the udder in cows (PI. XXXVIII) 

 has received considerable attention from sanitarians, owing to the 

 infection of the milk with the virus of tuberculosis. Accordino; to 



