MENSTRUATION. 575 



the menses were very scanty and irregular, or even entirely absent. 

 The menstrual flow is, in fact, only the external sign and accompa- 

 niment of a more important process taking place within. It is 

 habitually scanty in some individuals, and abundant in others. 

 Such variations depend upon the condition of vascular activity of 

 the system at large, or of the uterine organs in particular; and 

 though the bloody discharge is usually an index of the general 

 aptitude of these organs for successful impregnation, it is not an 

 absolute or necessary requisite. Provided a mature egg be dis- 

 charged from the ovary at the appointed period, menstruation pro- 

 perly speaking exists, and pregnancy is possible. 



The blood which escapes during the menstrual flow is supplied 

 by the uterine mucous membrane. If the cavity of the uterus be 

 examined after death during menstruation, its internal surface is 

 seen to be smeared with a thickish bloody fluid, which may be 

 traced through the uterine cervix and into the vagina. The Fallo- 

 pian tubes themselves are sometimes found excessively congested, 

 and filled with a similar bloody discharge. The menstrual blood 

 has also been seen to exude from the uterine orifice in cases of pro- 

 cidentia uteri, as well as in the natural condition by examination 

 with the vaginal speculum. It is discharged by a kind of capillary 

 hemorrhage, similar to that which takes place from the lungs in 

 cases of haemoptysis, only less sudden and violent. The blood does 

 not form any visible coagulum, owing to its being gradually exuded 

 from many minute points, and mingled with a large quantity of 

 mucus. When poured out, however, more rapidly or in larger 

 quantity than usual, as in cases of menorrhagia, the menstrual blood 

 coagulates in the same manner as if derived from any other source. 

 The hemorrhage which supplies it comes from the whole extent of 

 the mucous membrane of the body of the uterus, and is, at the same 

 time, the consequence and the natural termination of the periodical 

 congestion of the parts. 



