16 VETERINARY OBSTETRICS. 
The outlet of the Mare’s pelvis is limited above . 
by the apex of the sacrum and the base of the coccyx, 
and below by the ischial arch formed by the junction 
of the two ischia; and laterally by the upper surface of 
the ischia, and posterior border of the sacro-sciatic 
ligaments. The diameters are usually less than those 
of the inlet. 
The pelvis of the Cow is longer than that of the 
Mare, and not so vertical; the ischio-pubic symphysis 
is longer, and is very curved, making the floor concave 
Fic. 7. 
INLET OF THE PELVIS OF THE MARE. 
a 6, Supero-inferior, or Sacro-pubic Diameter; c¢ d, Superior Bis-iliac 
Diameter; ¢/, Inferior Bis-iliac Diameter; e 7, £4, Oblique, Ilio-sacral 
or Sacro-iliac Diameters ; J K, Middle Diameter. 
in every direction. Comparatively speaking, the bony 
structure is altogether more extensive. The sacral 
surface is more concave, and the sacro-sciatic ligaments, 
although narrower, are longer. Compared with its 
height, the Cow’s pelvis is less wide. 
The inlet being more oblique than in the Mare, 
the diameters are very unequal. 
