_Symptoms._ These are very indefinite, depending very much on the complications. Some loss or perversion of appetite, a licking of the soil or walls, eating litter, filth and even manure, a clammy mouth, a redness along the margin of the tongue, eructations or attempts to eructate, or actual vomiting, colicy pains which are usually dull until the bowels are implicated, more or less rumbling in the bowels, sometimes icterus, in other cases tympany, and nearly always tardy passage of hard and scanty mucus-covered fæces. The colics may be intermittent, appearing only just after food is taken, or they may be continuous, the animal pawing incessantly hour after hour. A slight hyperthermia and a distinct tenderness of the epigastrium and left hypochondrium to pressure are valuable symptoms. Percussion causes even keener suffering. If the gastric contents are abundant and fermentation active, death may ensue from gastric tympany. In other cases, the persistence of colics at the time of feeding, of impaired appetite, constipation and loss of condition are the main symptoms. In the last named cases the patient may die of marasmus. _Lesions._ In cases terminating in fermentation and fatal tympany the stomach is full; in other types it is empty of all but water, mucus, and perhaps some irritant contents, or decomposed food. The alveolar mucosa of the right sac and above all of the pylorus is red, congested, petechiated, macculated, thickened to double its normal thickness or more, thrown into rugæ, and covered with tenacious mucus. This mucus is highly charged with detached epithelial cells, and at different points the mucosa is abraded by their desquamation. The epithelium generally shows swollen, opaque cells. The red congested spots show active engorgement of the capillaries, and this is especially marked around the glandular follicles, with more or less formation of embryonic cells. The duodenum is often implicated with similar lesions of the mucosa and its epithelial layers, which may block the orifices of the pancreatic and especially of the biliary duct. In this case there is a yellowish discoloration of the liver, excess of pigment in the hepatic cells, and hemorrhagic spots in the liver and even in the kidneys. The urine may be yellow or reddish brown from the presence of bile or blood pigment. In ruptured stomach, spiroptera, bots, and other irritants, we find their characteristic lesions, and in petechial fever there is excessive and partly hemorrhagic infiltration of the mucosa and submucosa. In protracted cases ulcers may be present on both stomach and intestine. When it is a localization of some specific fever the characteristic lesions of that affection will be found.