THE PELVIS. 

 MARE. 



23 



COW. 



It will be seen from these measurements that no great practical utility 

 can be derived from pelvimetry, so far as averages are concerned ; as the 

 diameters of the pelvis must vary with the size and other peculiarities in 

 an animal's conformation ; so that we may have considerable differences. 

 In the Mare alone, Saint-Cyr found a difference in the supero-inferior 

 diameter of 2I- inches, and in the transverse diameter of 2% inches. 



With the view of determining the capacity of the pelvis of the living 

 animal at a given \\\t\q, external pelvimef?y has been resorted to. This 

 consists in ascertaining the distance between the angles of the haunch on 

 each side, that between the two ischial tuberosities, and that between the 

 coxo-femoral articulation and the highest part of the croup. To find out 

 the first, a piece of wood is placed vertically against each haunch, and the 

 space between them is measured ; for the second, a tape measures the 

 distance between the ischial tuberosities ; and for the third, a piece of wood 

 is placed horizontally across the summit of the croup, while another is 

 laid in the same direction along the trochanter and the ischial tuberosity, 

 the vertical distance between the two pieces giving the measurement. 

 Taking into consideration the shape of the pelvis, it has been calculated 

 that the transverse diameter of the outlet should be nearly equal to one- 

 fourth of the distance between the haunches added to that between the 

 ischial tuberosities ; while the supero-inferior diameter of the outlet is 

 supposed to be equal to three-fourths of the vertical distance separating 

 the coxo-femoral articulation from the summit of the croup. These 

 measurements only give the supposed diameters of the outlet ; but Ar- 

 loing, who has devoted much attention to pelvimetry in animals, points 

 out the means whereby the diameters of the inlet may be attained.* 



*■ The calculations and measurements are given in Saint-Cyr's " Traite d'Obstetrique Vet^rinaire," p. 21. 



