very fairly be compared with the intestines and the mesentery." For, as the intestine is bound down by the mesentery, so is this portion of the uterus attached to the spinal column by an ob- long membranous process ; lest by being too loose, and getting twisted, the passage of the yelks should be interfered with, in- stead of having a free and open transit afforded them as at present. The mesometrium also transmits numerous blood- vessels surcharged with blood, to each of the folds of the uterus. In its origin, substance, structure, use, and office, this part is therefore analogous to the mesentery. Moreover, from the fundus of the uterus lengthwise, and extending even to the infundibulum, there is a ligament bearing some resemblance to a tape-worm, similar to that which we notice in the upper part of the colon. It is as if a certain portion or stripe of the external tunic had been condensed and shortened in such a manner that the rest of the process is thrown into folds and cells : were you to draw a thread through a piece of intestine taken out of the body, and to tie this thread firmly on one side, you would cause the other side of the bowel to pucker up into wrinkles and cells ; [even so is it with the uterus of the fowl.] This then, in brief, is the structure of the uterus in the fowl that is laying eggs : fleshy, large, extensible both longitudinally and transversely, tortuous or winding in spirals and convolu- tions from the cloaca upwards, in the line of the vertebral column, and continued into the infundibulum.
EXERCISE THE NINTH.
Of the extrusion of the egg, or parturition of the fowl, in general.
The yelk, although only a minute speck in the ovary, gaining by degrees in depth of colour and increasing in size, gradually acquires the dimensions and characters that distinguish it at last. Cast loose from the cluster, it descends by the infun- dibulum, and, transmitted through the spirals and cells of the processus uteri, it becomes surrounded with albumen ; and this, without in any place adhering to the uterus (as was rightly observed by Fabricius in opposition to Aristotle), or growing by means of any system of umbilical vessels ; but as the eggs of
