OVULATION AND MENSTBUATION. 457 



or of any kind of influence from the male ; but it is possible 

 that, as held by many authorities, the discharge of ova, though 

 in no way dependent on sexual intercourse, may yet be hastened 

 by this. 



4. Menstruation. 



Menstr uation is the periodical discharge from the uterus of 

 a certain amo unt "of bloo d , mixed with mucus from the uterine 

 gla nds, and with epithelial and connective-tissue cells, der ived 

 from disintegration of the mucous membrane of the uterus 

 itself. 



There is a close connection between menstruation and ovu- 

 lation. Both processes commence at puberty, and last through- 

 out the child-bearing period. They both recur periodically; 

 and, further than this, the intervals are the same, and the two 

 processes occur, as a rule, simultaneously. The true nature 

 and extent of the connection between the two will be discussed 

 after the nature of the menstrual process has been considered 

 more fully. 



D uring the period of pregnancy ^that is^ during the whole 

 time th at an ovum <^t prnhvjn is dftvelnping withia the uterus, 

 menst ruation ceases, recorrTip nciTig mV or seven weeks after the 

 birthof the child. The normal occurrence of the menstrual 

 periods may also be affected by a variety of accidental or 

 pathological conditions, for the consideration of which reference 

 must be made to works dealing with obstetrics. 



Me nstruation, i.e. the actual disch arge from the uterus of 

 bloo d and other matters, is not an isolated process, but is the 

 terminal ac t of a series of changes, which occur at re gular 

 intervals Tirthe walls of the uteru s, and^jJ-which the sequence is 

 as follows^ 



In the quiescent condition the uterus is lined by a smooth 

 mucous membrane, of a soft, spongy consistence, and pale red 

 colour. It consists of a single layer of ciliated epithelial cells, 

 resting on a very delicate basement membrane, beneath which 

 is the connective-tissue layer of the mucous membrane. This 

 latter is about 1"5 mm. in thickness, and consists of connective 

 tissue, with very numerous connective-tissue cells, and traversed 

 by irregularly arranged muscle fibres. It is attached by its 

 outer surface to the muscular wall of the uterus. 



