EPITHELIAL TUMORS. 337 



as a rule, in the formation of cysts; and in those cases that are 

 superficial we may have ulcerations externally somewhat resem- 

 bling carcinoma. While adenoma is not malignant/it may become 

 so in certain cases and change into a cai-cinoma. We have observed 

 adenoma in most of the various glandular organs, upon the skin, 

 in the mucous membranes, in the mammary glands, in the salivary 

 glands, and thyroid gland. Tumors of the auus and stomach 

 deserve special mention. 



(a) Tumors of the Anal Glands. The rectum of the dog has 

 beside the ordinary cutaneous glands: 1. Glands of the anal 

 pouches. These are glands having a branch tube-shaped form, 

 located in the walls of the anus. 2. Acinous glands, which are 

 formed in the so-called anal protuberance. 3. Anal glands, which 

 are small, grape like bodies located between the lower bowel and 

 the anal mucous membrane. 



All these glands may become the seat of adenoma, but the latter 

 is mostly developed in the circum-anal glands. Sarcoma and 

 carcinoma occur quite frequently in the rectum of the dog. 



Tumors of the circum-anal glands, which are generally found in 

 old dogs, have been carefully studied by Siedamgrotzky. They 

 appear as round or irregular, firm tumors which are connected 

 closely with the skin, and produce more or less enlargement of 

 that part ; otherwise they are connected with their neighborhood 

 by a loose connective tissue. In the transverse section they appear 

 to be formed of yellowish-white or jellowish-red tissue, which is 

 similar to the circum-anal glands. As a rule, they are easily 

 removed. 



In some cases we have acute inflammation of the circum-anal 

 glands with a formation of abscess. The tumors may be easily 

 distinguished by the presence of pain, heat, and later fluctuation. 

 We also see on these occasions an inflammation of the anal pouches. 

 The anal pouches represent the caecal pouches, which vary in 

 size from a hazelnut to a walnut, and lie between the mucous 

 membrane and the muscular membrane. They contain within their 

 wails the above-mentioned glands and have only an external exit 

 by means of a very narrow canal. Inside we have a yellowish- 

 brown, thick fluid, which, as a rule is fetid. Various influence.^, 

 generally of a traumatic character, may cause inflammation of 

 these pouches and a retention of their contents. The anus be- 



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