=Symptoms.= In most cases lameness appears immediately the animal leaves the trevis, but, although this is more difficult to explain, lameness is sometimes deferred until the day after, or even two days after, shoeing. Though little marked at first, lameness may become so severe that the animal cannot bear the pain caused by the foot touching the ground. When this stage is reached general disturbance becomes marked, fever sets in, rumination stops, and appetite is lost. These symptoms point to the occurrence of suppuration. The pus, confined within the horny covering of the foot, causes very acute suffering and sometimes grave general disturbance; later it burrows in various directions, separating the podophyllous tissue from the horn, and ends by breaking through “between hair and hoof” in the region of the coronet. In exceptional cases, complications such as necrosis of the podophyllous tissue extending to the bone, and suppuration of its spongy tissue, may be observed. =Diagnosis.= When the farrier suspects he has pricked an animal the immediate withdrawal of the nail will remove any doubt, because bleeding usually follows. If the condition is only detected at a later stage, the early lameness having been misinterpreted, examination of the claw and tapping the clenches of the nails will cause the animal to show pain at a given point, thus indicating the penetration of the nail. Removal of the offending nail is painful, and is often followed by discharge of pus or blood-stained fluid, which clearly points to the character of the injury. In obscure cases the shoe should not be reapplied. When the horn wall is separated from the sensitive structures, there is marked general disturbance, and pus is discharging at the coronet, it is practically impossible to err in diagnosis. =Prognosis.= In cases of simple nail puncture the prognosis is hopeful, provided that the condition is at once diagnosed. The longer it remains unrecognised, particularly if complication like necrosis has occurred, the graver becomes the outlook. =Treatment.= In cases of simple puncture the nail should immediately be withdrawn and the animal placed on a perfectly clean bed to prevent the wound becoming soiled or infected. If lameness appear and become aggravated, the shoe should be removed and antiseptic poultices applied. In the majority of cases the lameness will then diminish, and in a few days completely disappear. In cases of discovery within the first few days the same treatment is applicable, and is often sufficient. If, on the contrary, pus is discharging at the coronet, if lameness is intense and the general symptoms marked, it may be needful to operate. The stages of operation comprise: thorough thinning of the horn in the shape of an inverted =V= over the affected portion of the wall, removal of the loose necrosed parts, disinfection of the wound, and the application of a surgical dressing covering the entire claw.