The biliary tract from its origin in fine intrahepatic radicles to the bladder and to the end of the common or intestinal ducts is the seat of many inflammations both acute and chronic, but since they are supposed to lead to damage to the liver and pancreas and to the production of gall stones, it is well to consider the system as a whole. As a matter of fact separate analyses of cholangitis, choledochitis and cholecystitis do not reveal different figures for each or for different orders. The vulnerability of this tract is found to be directly as the percentage of cirrhosis, to wit, the carnivores stand first, then the marsupials, ungulates, Primates and rodents; among the birds the order is Accipitres, Anseres, Struthiones, Psittaci, and Galli. It is difficult in most instances to evaluate the various possible etiological factors, but, due caution being exercised, gastrointestinal inflammation could be held responsible in seventeen of the total of fifty cases. In twelve of the seventeen this process was wholly or largely in the duodenum. The next factor was general infection, at the head of which pneumonia and “distemper” occupied about equal places. In marsupials, the streptococcal and streptothrical infections to which these animals are susceptible, was the prime factor. This group almost always has definite signs of stasis both in the liver and, as indicated by jaundice, in the general tissues. Pancreatitis was present in seven of the fifty cases and in five of the seven, enteritis was also found. Common duct stones were not observed. I shall have something to say about pericholangitis and pericystitis under the head of pancreatitis. TUMORS. The liver presents a good share of the tumors appearing in solid viscera but, with the exception of a few points, they offer little of interest. In the first place three angiomata have been seen and while they may not be tumors in the accepted sense of the word, may be considered briefly. A single cavernous angioma was seen in a goose. It occupied a large part of the right lobe but did not seem to affect mechanically the function of the organ since conditions wholly foreign to the liver were the cause of death. A leopard presented several small groups of telangiectatic angiomata lying mostly at portal spaces, a few also under the capsule. The liver of a thrush was likewise scatteringly beset with small angiomata. The original notes and recent examination do not reveal parasites or perivascular sarcomatous change.