TUMORS IN THE VAGINA AND PELVIS.--Tumors of various kinds may form in the vagina or elsewhere within the pelvis, and when large enough will obstruct or prevent the passage of the fetus. Gray mares, which are so subject to black pigment tumors (melanosis) on the tail, anus, and vulva, are the most liable to suffer from this. Still more rarely the wall of the vagina becomes relaxed, and being pressed by a mass of intestines will protrude through the lips of the vulva as a hernial sac, containing a part of the bowels. If a tumor is small it may only retard and not absolutely prevent parturition. A hernial protrusion of the wall of the vagina may be pressed back and emptied, so that the body of the fetus engaging in the passage may find no further obstacle. When a tumor is too large to allow delivery the only resort is to remove it, but before proceeding it must be clearly made out that the obstruction is a mass of diseased tissue, and not a sac containing intestines. If the tumor hangs by a neck it can usually be most safely removed by the ecraseur, the chain being passed around the pedicel and gradually tightened until that is torn through. HERNIA OF THE WOMB.--The rupture of the musculo-fibrous floor of the belly and the escape of the gravid womb into a sac formed by the peritoneum and skin hanging toward the ground is described by all veterinary obstetricians, yet it is very rarely seen in the mare. The form of the fetus can be felt through the walls of the sac, so that it is easy to recognize the condition. Its cause is usually external violence, though it may start from an umbilical hernia. When the period of parturition arrives, the first effort should be to return the fetus within the proper abdominal cavity, and this can sometimes be accomplished with the aid of a stout blanket gradually tightened around the belly. This failing, the mare may be placed on her side or back and gravitation brought to the aid of manipulation in effecting the return. Even after the hernia has been reduced the relaxed state of the womb and abdominal walls may serve to hinder parturition, in which case the oiled hand must be introduced through the vagina, the fetus brought into position, and traction coincident with the labor pains employed to produce delivery. TWISTING OF THE NECK OF THE WOMB.--This condition is very uncommon in the mare, though occasionally seen in the cow, owing to the greater laxity of the broad ligaments of the womb in that animal. It consists in a revolution of the womb on its own axis, so that its right or left side will be turned upward (quarter revolution), or the lower surface may be turned upward and the upper surface downward (half revolution). The effect is to throw the narrow neck of the womb into a series of spiral folds, turning in the direction in which the womb has revolved, closing the neck and rendering distention and dilatation impossible.