LESIONS IN ABDOMINAL CAVITY 141 



disease, and, accordingly, properly classed among the infectious 

 diseases. It is, indeed, unfortunate that all efforts up to the present 

 time have failed to demonstrate conclusively the exact definite 

 germ which produces the disease. More extensive work, however, 

 is being done every year, and workers in every government, state, 

 and college laboratory are making every effort to locate the exact 

 cause of the disease, and it seems but a question of a short time 

 until some one of these workers will discover the elusive organism 

 which has so far baffled every effort to locate it. 



Changes in Mesenteric Glands. — In connection with the ex- 

 amination of the intestines it would seem well to again call attention 

 to the examination of the chain of mesenteric lymphatic glands. 

 These glands are several in number, and form a row or chain 

 across the width of the mesentery which serves to anchor the intes- 

 tines to the abdominal wall. Normally, these glands are of a light 

 gray or pinkish color. In cholera they become much enlarged, 

 swollen, and decidedly discolored, as the result of hemorrhage into 

 their substance. 



Changes in the Liver, — There is a remarkable absence of any 

 very pronounced visible changes in the liver in a great percentage 

 of hog-cholera cases. The organ is often considerably swollen and 

 somewhat paler or more yellowish in appearance than normal, but 

 there is by no means the extensive series of changes in this organ 

 as a result of the infection that we might expect from the severity 

 and character of the disease. 



As a general rule, it may be stated that the liver is increased in 

 size, is somewhat swollen in outhne, the color is more pale than 

 normal, with a tendency to be yellowish, especially if there be 

 any marked biliary obstruction or inflammation of the bile-ducts 

 accompanying the disease. The organ is less firm than normal, 

 and cuts much easier with the knife than does the healthy liver. 

 Examination of the cut surface of the liver frequently shows it to 

 be bathed in a bloody fluid, and, when this is scraped away with 

 the back of the knife, we find that the normal markings of the 

 liver are somewhat obhterated and the organ has a peculiar 

 mottled appearance. 



There is also usually a more or less marked discoloration of 

 the tissue, due to the obstruction offered to the free escape of bile 



