Uterine Vessels 393 



The cavity of the uterus is small and triangular, the apex being con- 

 tinuous with the cavity of the cervix through the os internum, whilst the 

 superior angles receive the Fallopian tubes, or oviducts ; through the 

 oviducts the mucous membrane is directly continuous with the peri- 

 toneum ; hence, uterine injections escaping above may set up peritonitis. 



A titerine sound^-A.^^.^ for about two and a half inches into the normal 

 uterus ; it is marked in inches and fractions of an inch. The elbow in 



the sound is to render introduction more easy along the axes of outlet 

 and inlet of the pelvis. Its reckless use may cause abortion or inflam- 

 mation. 



The mucous lining- of the uterus consists of a basement mem- 

 brane covered with a single layer of columnar ciliated epithelium. It 

 is continuous with the lining of the Fallopian tubes, and, through the 

 cervix, with that of the vagina. Its deeper layer is very vascular, and 

 rests upon the muscular layer without the intervention of a submucous 

 stratum. The surface of the membrane is smooth and closely studded 

 with the openings of tubular, glandular inflections of the basement 

 membrane. The membrane swells during menstruation, being then 

 partially cast off ; in certain cases of dysmenorrhcea nearly the whole 

 of the lining comes away in pieces, with loss of blood. Much of the 

 discharge in leucorrhcea comes from the tubular glands. 



Vascular outgrowths of the mucous membrane may start into the 

 cavity and, growing downwards, become pedunculated. Such polypi 

 are a common source of haemorrhage and dysmenorrhcea. 



Supplies. The arteries come from the tortuous ovarian branches 

 of the aorta, and from the internal iliacs. They reach the uterus 

 between the layers of the broad ligament, and anastomose freely with 

 each other and across the median line They form a close and delicate 

 plexus in the mucous membrane, which eventually empties into venous 

 sinuses in the muscular wall. The uterine veins and ovarian veins 

 form a plexus in the broad ligament and enter respectively the in- 

 ternal iliac and the vena cava (right), or (left) the renal vein like the 

 spermatic veins. They communicate freely below with the vaginal 

 veins also. The dense plexus of ovarian and uterine veins is liable to 

 dilatation. 



The lymphatics pass from the mucous and muscular coats into a 

 delicate network beneath the peritoneum, and eventually enter the 

 pelvic and lumbar glands. 



The nerves are derived from the hypogastric plexus, and from 



