6go 



TEXT-BOOK OF PHYSIOLOGY. 



the uterus, the wide portion close to the ovary. The outer extremity of the 

 tube is expanded and subdivided, and presents a series of processes termed 

 fimbriae, one of which is attached to the ovary. The tube consists of three 

 coats an external or nbro-serous; a middle or muscle, the fibers of which 

 are arranged longitudinally and circularly; and an internal or mucous, which 

 is folded longitudinally. The surface of the mucous coat is covered with a 

 layer of ciliated epithelial cells, the direction of motion of which is toward 

 the uterus. 



The Uterus. The uterus is pyriform in shape and divided into a body 

 and neck. It measures, before the first pregnancy, about 7 cm. in length, 

 5 cm. in breadth and 2 J cm. in thickness. A frontal section of the uterus 



FIG. 346. OVUM OF A Cow. i. Zona 

 pellucida. 2. Cytoplasm, vitellus. 3. Nu- 

 cleus, germinal vesicle. 4. Xucleolus, germ- 

 inal spot. 5. Corona radiata. The radial 

 striation of the zona pellucida can not be 

 seen. (Stohr.) 



FIG. 347. FRONTAL SEC- 

 TION OF THE UTERUS, i. Cav- 

 ity of the body. 2, 3. Lateral 

 walls. 4,4. Cornua. 5. Cs 

 internum. 6. Cavity of the 

 cervix. 7. Arbor vitse of the 

 cervix. 8. Os externum. 9. 

 Vagina. (Sappey.) 



shows a central cavity which in the body is triangular in shape, in the neck 

 oval or fusiform (Fig. 347). At the upper angles of the uterus the cavity is 

 continuous with the cavity of each Fallopian tube. At the junction of the 

 body and the neck, the cavity presents a constriction, the internal os. The 

 constriction at the end of the neck is known as the external os. The walls of 

 the uterus are extremely thick and composed of non-striated muscle-fibers 

 arranged in a very complicated manner. The interior of the uterus is lined 

 by mucous membrane covered with cylindric ciliated epithelial cells, the 

 motion of which is toward the external os. Tubular glands are found in 

 large numbers in the mucous membrane lining the cavity, while racemose 

 glands are found in the mucous membrane lining the neck. Owing to the 

 flattening of the uterus from before backward the walls are almost in contact 

 and the cavity almost obliterated. 



