UTERUS. 



297 



Epithelium. 



-'- Gland. 



-Mucosa. 



and circular, and an outer longitudinal. The uterine muscles are smooth 

 sometimes branched. During pregnancy they increase in number and in 

 length to three or four times their ordinary dimensions. Except in the 

 peripheral part of its lower half the uterus contains little elastic tissue. 

 There the elastic elements are at right angles with the course of the muscle 

 fibers. They increase during the first half of pregnancy and decrease 

 in the latter half (except in the outer connective tissue). 



There is no submucosa; epithelial pits or uterine glands extend to the 

 muscle layer and occasionally enter it. They are vertical tubes, some- 

 times branched, which 

 have a tortuous course 

 in their deeper part. 

 Often two or three 

 unite so as to have a 

 common outlet. Their 

 distance from one 

 another, the extent of 

 their flexures and their 

 relation to the muscu- 

 laris are features sub- 

 ject to pathological 

 changes. Cystic dila- 

 tations are common 

 especially in older 

 persons. The glands 

 produce no specific 

 secretion. They are 

 lined with simple col- 

 umnar epithelium 

 sometimes ciliated, in 

 all respects like that 

 of the uterine cavity. 



Often cilia are absent from the uterine epithelial cells, which is said 

 not to be due to faulty preservation but to the* fact that the ciliated cells 

 occur singly or in groups. According to a recent estimate only T V or 

 ^V of the cells are ciliated; and from observations on certain animals it 

 is suggested that cilia are present only in certain functional conditions, at 

 other times being absent. 



In the cervix, mucus-producing cells occur, especially in the out- 

 pocketings of epithelial pits, thus forming the branched cervical glands. 

 They discharge a secretion which occludes the canal of the cervix during 



FIG. 341. Mucous MEMBRANE OP THE RESTING UTERUS OF A 

 YOUNG WOMAN. X 35. (After Bohm and von Davidoff.) 



