396 PHILOSOPHY OF ZOOLOGY. 
When the ovum bursts from the corpus luteum, or 
gland in which it has been prepared, it enters the Oviduct, 
or Fallopian Tube, through which it is conveyed to the 
uterus. The extremity of the oviduct, next the ovarium, 
is somewhat funnel-shaped, and its margin is irregularly 
divided into leaves, or fimbriz. This structure is con- 
sidered as useful in aiding the expulsion of the germ from 
the corpus lutewm, and in receiving it more readily into the 
tube. The oviduct itself has walls of a cellular substance, 
with abundance of bloodvessels, and traces of muscular 
threads. It is more or less tortuous in its course, and 
terminates by an opening in the upper part of the cavity 
of the uterus. Both oviducts open, im some cases, very 
near each other, while, in other instances, they are more 
remote. 
The Uterus, or matrix, exhibits a great variety of shape 
in different quadrupeds. In general, however, it 1s length- 
ened in the direction of the body, receiving, at its summit, 
the oviducts, and terminating below in the vagina. Its 
walls are remarkably dense, and they are liberally supplied 
with bloodvessels, absorbents, and nerves. The propor- 
tion between the size of the cavity and the thickness of 
the walls, is likewise very various. ‘The cavity itself ex- 
hibits several remarkable peculiarities. 
In the most simple form of the uterus, the cavity is 
somewhat pear-shaped, and the oviducts enter it at its lar- 
gest end, by very small openings. This shape prevails in 
the human race, the apes and sloths. It is called Uterus 
simplex. 'The next shape, in point of simplicity, is where 
the cavity divides at its summit into two processes, or 
horns, as they have been called. These are either straight, 
or variously convoluted, and terminate in the oviducts. 
This kind is termed Uterus bicornis, and may be seen in 
the dog, hedgehog, and the ruminating quadrupeds. In 
