610 GENITAL ORGANS OF THE SOW 
have a depression on the free surface. The neck is about an inch and a half (ea. 
4 cm.) in length; its lumen is closed by reciprocal prominences and depressions of 
the mucous membrane. The external uterine orifice is in the ventral part of the 
vagina. 
The vagina is three or four inches (ca. 8 em.) long. Its ventral part contains 
numerous lymph follicles. 
The vulva is an inch or more (ca. 2.5-3 em.) in length. There is a very small 
diverticulum behind the urethral orifice. The glandule vestibulares majores are 
inconstant; when present, they may be about the size of a small bean. The labia 
are thick and the ventral commissure is pointed and projects downward. 
The clitoris is short, and the glans is concealed in the fossa clitoridis. 
The mammary glands, two in number, are relatively large, and are approxi- 
mately globular, but flattened on the septal side. 
GENITAL ORGANS OF THE SOW 
The ovaries are concealed in the bursa ovarii, owing to the large extent of the 
mesosalpinx. They are more rounded than in the bitch, and have a distinct hilus. 
They may be situated at or near the lateral margin of the pelvic inlet, as in the cow; 
but their position is quite variable in animals which have borne young and they may 
be only an inch or two behind the kidney. The surface commonly presents rounded 
prominences, so that the gland usually has an irregular lobulated appearance; 
the projections are large follicles and corpora lutea. Mature follicles may have a 
diameter of about a third of an inch (ca. 7-8 mm.), and corpora lutea may be found 
which measure half an inch or more (ca. 12-15 mm.). 
The uterine or Fallopian tubes are long (ca. 15-30 em.), and less flexuous than 
inthe mare. The fimbriated extremity forms an ampulla and has a large abdominal 
opening. The uterine end shades insensibly into the small extremity of the cornu 
of the uterus. 
The uterus presents several striking features. The body is only about two 
inches (ca. 5 em.) long. The horns are extremely long and flexuous, and are freely 
movable, on account of the large extent of the broad ligaments. In the non- 
pregnant animal they are arranged in numerous coils and appear somewhat like 
thick-walled small intestine. They may be four or five feet (1.2-1.5 m.) in length. 
The extremities of the horns taper to about the diameter of the uterine tubes. The 
neck is remarkable for its length (ca. 10 em.) and the fact that it is directly con- 
tinued by the vagina without forming any intravaginal projection. When slit open, 
peculiar rounded prominences are seen on its interior; some of these dovetail and 
occlude the cervical canal. They are continuous behind with folds of the mucous 
membrane of the vagina. The broad ligaments contain a large amount of unstriped 
muscle; they also contain a large lymph gland near the ovary.!. In the upper part 
of the ligament the muscular tissue forms a rounded band termed the round liga- 
ment. In an adult sow of full size it is about six inches (ca. 15 em.) long; its 
anterior end forms a blunt projection and posteriorly it ends in the subserous 
tissue at the internal inguinal ring. The medial layer of the broad ligament is 
continuous with the lateral ligament of the bladder. 
The vagina is about four or five inches (ca. 10-12 em.) long in a sow of medium 
size. It is small in caliber, and has a thick muscular coat which consists of cireular 
1 The changes in form and position of the uterus during pregnancy are similar to those men- 
tioned later in the case of the bitch (p. 618). 
