The peptic stomach in the different animals is subject to a great variety of tumors. In many of the recorded cases, however, the true nature of the tumor has been left uncertain. =Sarcoma.= In the =horse= this is the common tumor of the pylorus, and less frequently it is found on the cardia and body of the stomach, especially on the greater curvature. These are usually firm and resistant, though sometimes soft and friable; they tend to swell out in lobules, and show areas of ulceration, or even suppurating excavations opening through the mucosa. In some instances, however, they start under the serous coat, and the ulcerous surface may open into the peritoneum. At other times they are but a local manifestation of a general affection. In the =dog= multiple sarcomata have been found on the stomach varying in size and easily mistaken for recent tubercles. In these cases the small round cells were especially numerous in the centre of the tumor rendering it soft and predisposing to degeneration. =Papilloma.= In the horse these are found as branching or filamentous dependent projections from the mucosa of the left sac having evidently started from the sores formed by the attachment of the œstrus larvæ. They are also found around the pylorus and of such size as to seriously obstruct that orifice (Stadler). =Lipoma.= Fatty tumors have been seen on the stomach of the =dog= and =horse= in the submucosa. =Adenosarcoma.= This formation in the =horse= leads to a thickening of large patches of the mucosa. It also grows out in mushroom like masses, or is irregularly lobulated. =Epithelioma.= In the =horse= epithelioma has been found at the pylorus and on the great curvature of the stomach. It usually grows out as a rounded mass varying in size from an egg to an infant’s head, and may be even a diffuse thickening of the mucosa. Microscopically the individual lobules, are composed of cylindroid cells surrounding a central mass of epidermoid cells. The stomach may be greatly contracted, and the surface of the neoplasm, ulcerated or even excavated. In the =dog= similar formations are found. =Carcinoma.= In =cattle= _Scirrhus_ of the abomasum is described. Small tumors rise to a height of ½ to 3 inches, and are closely packed together so as to assume polygonal forms. The surface is smooth, or perforated by orifices leading into ulcerous or suppurating cavities. On section the mass shows a fibrous or a lardaceous consistency. They are most common in the pyloric region, and may partially obstruct this orifice. _Symptoms._ These are necessarily obscure. In the =horse= periodic gastric indigestions and colics may be the sole indications, which are certainly not pathognomonic. In other cases, have been noticed: vertigo, salivation, impacted gullet, and blackish, sanguinolent fæces due to ulceration and hemorrhage from the tumors.