THE FEMALE ORGANS OF GENERATION. 243 



transversely striated muscular fibres of the urethral muscles. 

 The external fibrous coat of the urethra consists of wavy con- 

 nective-tissue fasciculi, which have a longitudinal and circular 

 course. 



The uterus possesses an external covering of serous mem- 

 brane, the peritoneum ; anteriorly it is more intimately con- 

 nected with the organ than posteriorly, while at the sides the 

 layers are separated, in order to permit the passage of blood- 

 vessels, lymphatics, and nerves into the uterine substance. 

 The tissue composing the greater part of the uterus is formed 

 of smooth muscular fibres, the arrangement of which is very 

 irregular, but three more or less distinct layers have been de- 

 scribed. The external one, which is relatively thin, consists 

 mostly of fibres running longitudinally, although many circu- 

 lar fasciculi are seen. The middle layer exceeds the others in 

 thickness, its fibres take a longitudinal, transverse, or oblique 

 direction, while the internal layer is essentially circular, and 

 forms the sphincters of the uterus. The contractile elements 

 of these muscular layers are intimately united together by a 

 cementing substance, forming fasciculi or bundles, which are 

 again held together by connective tissue in which elastic fibres 

 are found. The shape of the cells in the normal uterus is fusi- 

 form, frequently very long, and in transverse section round or 

 oval, with several angles. The nucleus is always single, rod- 

 like or oblong in shape. 



The mucous membrane lining the uterus is closely connected 

 to the muscular tissue. It has no connective-tissue framework 

 of fibres, but its structure resembles the stroma of lymphoid 

 organs, in which the framework is made up of spindle and 

 fusiform cells. The surface of this membrane varies in differ- 

 ent parts ; at the fundus and body it is smooth, except at the 

 orifices of the Fallopian tubes, where there is a slight folding ; 

 in the canal of the neck it is thrown into numerous branching 

 folds, the plica palmatce. At the upper end of the isthmus of 

 the cervix a distinct border indicates the termination of the 

 mucous membrane of the body. The epithelium covering this 

 portion of the membrane is columnar in shape, and provided 

 with short cilia. There are found in the mucous membrane 

 of the fundus and body numerous tubular glands, which are 

 either simple tubes or they divide about their middle, and ter- 



