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paired with the formation of an extensive bony deposit bulging into the 

 passage of the pelvis. The displacement of the ends of the broken bone 

 is another cause of constriction and between the two conditions the 

 passage of the fcetus may be rendered impossible without emhryotomy. 

 Fracture of the sacrum (the continuation of the back-bone forming the 

 croup) leads to the depression of the posterior part of that bone in the 

 roof of the i)elvis and the narrowing of the passage from above down- 

 ward by a bony ridge iiresenting its sharp edge forward. 



In all cases in which there has been injury to the bones of the pelvis 

 the obvious precautioa is to withhold the mare from breeding and to 

 use her for work only. 



If a mare with a pelvis thus narrowed has got in foal inadvertently, 

 abortion may be induced in the early months of gestation by slowly 

 introducing the oiled finger through the neck of the womb and follow- 

 ing this by the other fingers until the whole hand has been introduced. 

 Then tiie water-bags may be broken, and with the escape of tbe liquid 

 the womb will contract on the solid foetus and labor pains will ensue. 

 The foetus being small it will pass easily. 



TUMOES 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 foetus. Gray mares, which are so subject to black pigment tumors 

 {melanosis) on the tail, anus, and vulva, are the most likely to suffer 

 from this. Still more rarely the wall of the vagina becomes relaxed, 

 and being i^ressed by a mass of intestines will protrude through the lips 

 of the vulva as a hernial sac, containing a part of the bowels. Where 

 a tumor is small it may only retard and not absolutely prevent parturi- 

 tion. A hernial i)rotrusiou of the wall of the vagina may be pressed 

 back and emptied so tbat the body of the fcetus engaging in the passage 

 may find no further obstacle. When a tumor is too large to allow de- 

 livery tbe 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 hang- 

 ing towards the ground, is described by all veterinary obstetricians, 

 yet it is very rarely seen in the mare. The form of the foetus can be 

 felt through the walls of the sac, so that it is easy to recognize the condi- 

 tion. Its cause is usually external violence, though it may start from 

 an umbilical hernia. When the period of parturition arrives, the first 

 eftbrt should be to return the fcetus within the proper abdominal cavity, 



