_Symptoms._ A white or brownish yellow deposit in the last urine discharged collects on the floor. Cloudy urine. Passage of crystals—round—or angular. Colic. Lameness in one or both hind limbs. Arched back. Sensitive loins. Pain paroxysmal. Attempts to urinate. Little passed but often with drops of blood. Sudden relief when the calculus enters the bladder. Retained in the kidney it may cause no suffering in meat producing animals, but in horses it usually causes stiffness or lameness especially under violent effort. Also hematuria; blood globules are found in the deposit when placed under the microscope. There may be sepsis and specially cloudy offensive urine. _Diagnosis_: May be confounded with renal tuberculosis, or sarcoma or oxaluria. Examine for bacillus, small cells, or oxalate of lime or oxalic acid. _Prophylaxis._ In the early stages give succulent, watery food, ensilage, roots, potatoes, spring grass, and water ad libitum. _Treatment._ Salt may tempt the patient to drink. Nitro-muriatic acid is a solvent and antiseptic. Or alkalies with salicylate of soda. Also tonics. Quiet pain by morphia and other anodynes. Use piperazine. These failing, an operation on the kidney may be considered. HYDRO-NEPHROSIS. A common result of calculus or other obstruction, causing increasing pressure of urine in the pelvis and absorption of the parenchyma, and finally leaving a mere urinous sac. RENAL TUMORS. 1. _Non-malignant_: Fibroma. Lipoma. Angioma. Adenoma. Papilloma. 2. _Malignant_: Sarcoma. Carcinoma. RENAL PARASITES. Echinococcus: Herbivora, Omnivora. Bilharzia Crassa: Egyptian cattle. Strongylus Gigas: Horse, ox, dog, man. (Cysticercus Tenuicollis: Ruminants: Pig). Tænia serrata: Dog. Pelvis. Sclerostoma equinum: (renal arteries, _kidney pelvis_), soliped. Stephanurus dentatus: Pig, (pus cavities). Trichosoma plicata: (Urinary bladder), dog. T. felis: (Cat), bladder. Indetermined embryos: Kidneys, dog; small tumors. Cytodites nudus: Kidneys; hens. Œstrus, (Gast. Hemorrhoidalis): Bladder walls: horse. Mucorimyces: Kidneys; dog. Coccidia: Kidney, Horse, dog, goose. INJURIES OF THE URETERS.