PARTURITION. 



491 



two near the umbilicus. In other cases, in the mare, the chorion becomes 

 detached from the uterus almost immediately after the expulsion of the 

 ^oetus and comes away with the cord still intact. It is then ruptured later 

 by the struggles of the foetus itself. The mare may step upon some portion 

 of the membranes when the foal is attempting to get up, and the foal, in 

 falling, throws its weight upon the cord in such a way as to rupture it. 



After it ruptures, the behavior of the parts when left undisturbed is 

 interesting and highly suggestive of the degree and character of interfer- 

 ence demanded upon the part of the attendant. One of the most promi- 

 nent effects of the rupture of the cord by linear tension, or by laceration 

 by the teeth of the mother, is the promptness with which hemostasis is 

 brought about, so that as a rule there is but little hemorrhage, appearing 



DOUSAL (or back) PRESENTATION. 



usually to not exceed the amount of blood lying in the umbilic veins out- 

 side the umbilic ring. 



XI. Various Presentations Illustrated. 



The presentation results from the part of the foetus which first offers 

 itself at the pelvic inlet — that region of the young creature which the hand 

 of the obstetrist immediately meets on being passed into the os, and which 

 is directly opposite the inlet. In this sense the head, fore feet, hind feet, 

 croup, etc., are said to be presented, according as one or other of them 

 first offers itself on exploration. 



These presentations are extremely variable, as any part of the foetus 

 may occupy this situation ; though so far as description and comprehen- 



