=Gastric Ulcer.= Ulceration of the mucous membrane of the stomach, is much less frequent than of other portions of the intestinal canal, except as a result of the corrosive action of poisons.[20] A peculiar kind of ulcer, however—rare in this country, but said to be common on the Continent of Europe and in England—is sometimes found, which is of interest, from its occurring in tissues otherwise healthy, and often leading to a rapidly fatal termination. Rokitansky terms it the _perforating gastric ulcer_, from its marked tendency to perforate the walls of the stomach. It is situated in the region of the pylorus, and more frequently at the posterior surface and near the lesser curve. It is of a circular form, of three to six lines in diameter, and with as sharp edges as if a round piece of the walls had been punched out; the edges being bevelled off, however, from within, leaving the peritoneal opening less than that in the muscular or mucous coats. Being usually situated near the lesser curve of the stomach, some of the larger blood-vessels are liable to become involved, giving rise to hæmorrhage more or less severe. While but a single ulcer of this description is generally found, two, three or more, may be present. A peculiarity of this form of ulcer, consists in its not being dependent upon irritation or inflammation, but rather upon a loss of vital assimulative power in the part affected. This form of ulcer may heal at any time previous to perforation, and it is not uncommon to find a cicatrix in the mucous membrane of the stomach which has probably arisen in that way. Gastric ulcer is much more frequent in females than males, and is mainly a disease of middle and advanced life. =Hæmorrhagic Erosions.= The appearance of the stomach, where there has been frequent vomiting of blood from this cause, is thus described by Rokitansky: “There are several roundish spots of the size of a pin’s head or pea, or narrow elongated streaks at which the mucous membrane appears dark red, lax, soft and bleeding, and presenting a depression in consequence of loss of substance or slight erosion. This condition is invariably accompanied by hæmorrhage, the effused blood being mixed, in a more or less altered state, with gastric mucus. The erosions are often very numerous, studding, perhaps, every part of the stomach except the fundus, the pylorus being their chief seat.” This condition of the stomach is not peculiar to any form of disease, or age, but is frequently associated with intemperance. It is rarely fatal, except by inducing some other lesion of the stomach, or by being united with some more general malady.