As with fractures of the os pedis and the os coronæ, so with this exact diagnosis is difficult--we may say almost impossible. With a history of violent injury, however, some little regard may be paid to a continued heat and tenderness of the foot, and a distinct inclination on the part of the animal to go on the toe. Even when the fracture is the result of a prick, and the bone is plainly felt with the probe, we still cannot be positive as to fracture. _Reported Case_.--'The animal was a Hungarian, a troop-horse in the 3rd Hussars (G. 15). On November 22, 1881, on the march from Norwich to Aldershot, the horse suddenly made a violent stumble, very nearly coming on to his knees. The rider declared that he put his foot on a stone. The accident caused great lameness in the near fore-leg, and the horse had to be led the remainder of that day's march. On the following day he was also led; but, after going some sixteen or eighteen miles, he was so lame that he was left at the nearest billet (in Edmonton). He was here attended by Mr. Stanley, M.R.C.V.S., of Edmonton, who pronounced it a case of navicular disease. I first saw the animal on December 1, 1881, and quite agreed with Mr. Stanley that it was a case of foot lameness, though, from the horse's former history, I could not think it a case of ordinary navicular disease. I diagnosed it a case of fracture, without displacement, either of the os coronæ or the navicular bone, but was more inclined to the former than the latter. This was after a full hour's examination. I failed to find any heat in, or any flinching by manipulation of, any part of the limb; but, in walking, the horse was excessively lame, going on the toe, and, indeed, trying if possible to keep the foot entirely off the ground.