Part 299

The fœtal kidney is divided by furrows into a number of polygonal areas, each of which is the base of a pyramidal lobe or renculus. These furrows usually disappear before or soon after birth in the foal, although traces of them are sometimes seen in the adult.

Footnote 138:

In the kidney of the horse the renal columns dip in between the pyramids very superficially as compared with the arrangement in the human kidney. Breuer states that the pyramids are 40 to 64 in number, and are arranged in four rows. Only the middle ones are distinct.

Footnote 139:

The crest is the result of fusion of the papillæ or apices of the pyramids in the embryo.

Footnote 140:

This is commonly termed the fundus by veterinarians, but is not the homologue of the fundus of the human bladder.

Footnote 141:

This would correspond to the fundus vesicæ of man.

Footnote 142:

From the standpoint of comparative anatomy the term “adrenal” seems decidedly preferable to “suprarenal.”

Footnote 143:

This is a remnant of the gubernaculum testis of the fœtus.

Footnote 144:

The tunica vaginalis is not a part of the scrotum in the strict or narrow sense of that term, but is included here on practical grounds.

Footnote 145:

Sometimes one vesicula or both are very large in the gelding. The writer has seen four cases in the dissecting room, three of which were bilateral, the other unilateral. The vesicula resembled the urinary bladder in appearance and contained about a quart of thick, amber-colored secretion.

Footnote 146:

It has been customary to divide the pelvic part of the urethra into prostatic and membranous parts. These terms apply well in human anatomy, but have no special value in comparative anatomy. In the horse a prostatic part hardly exists, unless we assume that it and the neck of the bladder together are only about an inch in length. There is no membranous part in the sense in which that term is used in regard to man.

Footnote 147:

The statement often made that it acts as a sphincter of the bladder is a hypothesis of doubtful plausibility. In material hardened in situ, in which the internal urethral orifice is tightly closed, the urethral muscle apparently takes no part in the closure.

Footnote 148:

This is clinically important, since enlargement of the prostate may interfere with micturition.

Footnote 149:

These terms apply properly only when the adjacent viscera are removed and the ovaries are actually “suspended” by the broad ligaments. When the ovary is in its natural position, the surfaces are dorsal and ventral, the former corresponding to the “external” surface if the free border is directed outward, to the “internal” if the free edge is medial.

Footnote 150:

The Fallopian tubes may be regarded, both in structure and morphology, as prolongations of the uterus (McMurrich).

Footnote 151: