The _symptoms_ are by no means clear, unless the injury result from external traumatism, or when it can be detected by rectal exploration. There may be blood staining of the urine, stiffness of the loins, lameness in one hind limb, tenderness of the lumbar vertebræ and of their transverse processes on pinching, frequent straining to pass urine, a disposition to remain recumbent, pain and groaning when rising, or when turned in a narrow circle. Under rectal examination the blocked ureter may sometimes be recognized, its cystic end shrunken and empty, up to the seat of obstruction, and its renal end, from the hypersensitive seat of obstruction forward, full, rounded, elastic and firm. If the ureter has been ruptured, it may be impossible to distinguish it, but the presence of urine free in the peritoneum may be detected through the rectum as it may often be through the abdominal walls. Sometimes the urine infiltrates the subperitoneal connective tissue, and forms a pasty swelling on the loin or flank. In either case a hollow needle inserted will draw off a liquid having an urinous odor. That this urine has escaped in front of the bladder may be safely inferred from the continued discharge of urine by the urethra and by the absence of cystic swelling, heat and tenderness. If the kidney can be reached by rectal exploration it is felt to be firm and resistent up to the period of rupture of the ureter. In case of obstruction by calculus, crystals and even small calculi may be passed in the urine, there is usually a history of previous attacks of renal colic, and the suffering is manifestly extreme. In case of worms (strongylus gigas) the use of the centrifuge on the urine, may possibly secure in the sediment specimens of its ova. The existence of tumors or tubercles can usually be clearly made out. _Treatment_ will be as varied as the lesion. Simple ureteritis may be met by wet compresses, sinapisms, and internally by balsams and anodynes. Calculi and parasites may be passed with some aid perhaps from fomentations, antispasmodics, and diluents. Obstinate cases can only be successfully met by surgical interference. The resulting wounds in the ureter, like ruptures, perforating ulcers and strictures may be met by Van Hook’s “_lateral implantation_”: the divided cystic end of the ureter is ligatured and on the cystic side of the ligature a longitudinal incision is made, large enough to admit the divided extremity of the renal portion, and through each of the two sides of this last a fine ligature is passed; these ligatures are then passed into the lumen of the cystic portion of the ureter through its longitudinal incision and brought outward through its walls; next the renal end is inserted into the incision in the cystic end and the two are firmly sewed together by the two ligatures. When a small portion of an ureter must be excised it may sometimes be possible to save a valuable animal by such an expedient.