424 



COMPARATIVE ANATOMY 



their way up the tubes against the action of these ciHa; but the walls 

 of the tubes have strong circular and longitudinal muscular layers, so 

 that it is possible that spermatozoa are carried up the tube by peristaltic 

 waves. The blood supply of the tubes comes from ovarian and uterine 

 vessels. The nerves are sympathetic. (Fig. 347) 



Disinteg^ating._l^^l^!Kl. f iiJ. 

 epithelium. Va-V-;,'?^' vj v,' •<■' ■* 



Blood vessel, 



-4^^S 



£V^''\-' 



¥'^T 



"Surface epithelium. 



"0 6;;^ •■••'■ 5 • ='!■•• '■•■"■"« a f-t«' :3?T'^'i^^^''^-^" Disintegrating 



Uterine gland. '-•'■^'^':-)(^i>7^%^^^^ P'|-^ i^V^'-t^''*""" ^P'^'^s^^"™- 



Cystic tubule. 



Blood vessel.— ". 



, Pit-like depression. 



Bifurcating tubule. 



— Coiled tubule. 



-1%-yjf^^ Blood vessel. 



Muscularis. 



Fig. 349. — Mucous membrane of a virgin uterus during the first day of menstruation. 

 X30. (From Bremer's "Text Book of Histology," after Schaper.) 



The Uterus. The uterus is a median pear-shaped organ suspended 

 in the broad ligament. Round and uterosacral ligaments form additional 

 supports. The body of the uterus is normally bent forward so that it 

 rests upon the bladder. By a constriction, the isthmus, the uterus is 

 divided into an upper body and a lower cervix. Its cavity is connected 

 with that of the vagina below and those of the paired uterine tubes above. 



The cavity of the uterus is lined with a simple ciliated columnar 

 epithelium, from which numerous tubular glands of unknown function 



