=Catheterization of the Cow and Heifer.= The operation is often very difficult in the cow, by reason of the small size and undilatability of the urethra, and by the presence of two blind ducts (canals of Goërtner) above and to the two sides of the urethral opening. The thin rigid upper margin of the orifice projects down over it in a valvular manner so that the catheter will almost always find its way into one of the blind sacs. By introducing the tip of the index finger beneath the valvular fold and into the opening of the canal, the catheter may be directed beneath it and into the bladder. An apparatus consisting of a series of ribs of spring wire arranged in the form of a funnel and converging at one end to a point has been devised to insert into the urethral orifice, and guide the catheter which is passed through it. =Catheterization of the Bitch.= The operation is rendered difficult by the narrowness of the passage, and the puckers and folds of the vaginal mucosa which serve to hide the urethral orifice. A small catheter like that used on the male is used or a short metallic catheter may be substituted. By directing this forward exactly in the median line of the floor of the vulva, with gentle pressure downward it may be made to enter the urethra. In case of special difficulty a bivalve speculum may be resorted to, to efface the mucous folds and reveal the orifice. ACUTE PROSTATITIS AND HYPERÆMIA OF THE PROSTATE. Causes: In dogs, house life, overfeeding, compulsory retention of urine, and fæces, constipation, proctitis (rectitis), piles, calculi, strangury, uric acid, urethral ulceration or stricture, rude catheterization, chill, generative excitement to excess, secondary abscess or infection. Forms. Lesions: follicular, interstitial, circumscribed and diffuse suppuration. Symptoms: frequent straining urination, rectal palpation, incontinence of urine, costiveness, tender perineum, dullness, recumbency, fever, pus in urine, collapse of swelling, fistula. Diagnosis. Prognosis: grave. Treatment: laxatives, mercurials, salines, leeches, acid laxative, non-stimulating, camphor, bromides, ergot, witch hazel, opium, belladonna, enemata of cold water, or ice suppository, catheterization, perineal incision, antiseptics.