562 MENSTRUATION. [c HAP. XXX IX. 



from the numerous blood corpuscles it contains, and is perfectly 

 fluid,, as it is free from fibrine, a character which distinguishes it 

 from ordinary blood. Besides blood-corpuscles, it contains a num- 

 ber of small, pale granular cells, and large corpuscles, containing 

 numerous small oil-globules, the so-called granular corpuscles. 



Dr. Letheby has published an analysis of menstrual fluid which 

 had accumulated to the extent of forty ounces, in consequence of 

 an imperforate hymen. It was thick and black, and it contained 

 no fibrine. Under the microscope were detected altered blood 

 corpuscles, exudation or granular corpuscles, mucous cells, epithe- 

 lium, and granules. 



Water . 857*4 



Solid matter . 142-6 



Fat , , 5-3 



Albumen 69'4 



Globuline 49-1 



Haematin . ....... 2'9 



Salts -i * ; 8-0 



Extractive matter . . . . . ..! . 67 



Maturationof Ova, and their Discharge from the Graafian Follicle. 

 The most important of the phenomena, however, accompanying 

 menstruation, is the maturation and discharge of ova from the 

 ovary. At these periods, a Graafian follicle becomes enlarged, pro- 

 jecting considerably from the surface of the ovary, and distended 

 with fluid. Its wall becomes thin at one point, where it at length 

 gives way, and the contents of the follicle escape into the Fallopian 

 tube. The ovum has but rarely been detected in the Fallopian 

 tube ; which is scarcely to be wondered at, when we consider its 

 small size, and the very few cases in which we have an opportunity 

 of searching for it with a chance of success. It has, however, 

 been actually seen in one case in the human female examined by 

 Dr. Letheby, and in another by Mr. Hyett. In animals, it may be 

 detected without difficulty, although it is only of late years that 

 the escape of the contents of a Graafian follicle at each menstrual 

 period has been placed beyond a doubt. We owe to Dr. Robert 

 Lee, observations, made so long ago as the year 1831, which 

 established the fact of the rupture of a follicle, and the escape of its 

 contents, at each recurrence of menstruation. Ova have been 

 detected in the ovaries at a very early age. 



Dr. Ritchie states, that, even during childhood, there is a con- 

 tinual rupture of ovisacs and discharge of ova taking place ; but it 

 is not until the period of puberty that the number of ovisacs 



