566 



UTERUS AND ITS APPENDAGES. 



stance has the appearance of a tissue which is 

 in a low state of vitality. 



It is probable that the presence of this coat 

 within the follicle has been the cause of most 

 of the differences of opinion which have ex- 

 isted regarding both the seat and the nature 

 of the yellow portion of the follicle of preg- 

 nancy. It seems to have been assumed, with- 

 out further examination by many who have 

 written upon this subject, that the coat last 

 described is one of the coats originally com- 

 posing the Graafian follicle ; whereas it is 

 formed by the metamorphosis of the blood-clot, 

 already described as occupying the centre of 

 the follicle before even the ovum escapes. I 

 have seen very distinctly the fibrillation of 

 this clot soon after the follicle has closed. It 

 is then found to be gradually becoming pale, 

 the red particles disappear by degrees, the clot 

 adheres firmly to the inner surface of the 

 ovisac, and the mass is converted into the low 

 form of tissue just described, which ma)' either 

 take the condition of a membrane lining the 

 cavity and leaving a central space filled by 

 transparent fluid, or the whole may be con- 

 verted into a solid body. Either of these 

 forms may be observed, and the knowledge 

 that each may occur disposes of the specu- 

 lative question as to the time when the cavity 

 of the follicle is obliterated. 



On the other hand, the yellow coat which has 

 been often described by authors as altogether a 

 new formation, deposited either between or 

 external to both of the follicular coats, can be 

 most easily traced through all its phases, be- 

 ginning in the ascending vesicle, as the original 

 ovisac ; its structure filled with nucleated cells, 

 which gradually become charged with oil 

 droplets until the whole tissue assumes the 

 peculiar yellow which is so distinct about the 

 time of bursting of the follicle. And this 

 colour it never loses until the time of its 

 comj 



all the subsequent changes 

 same anatomical structure and the same rela- 

 tive position of parts is preserved. 



In the original preparation from which fig. 

 387. was taken, nothing served to distinguish 

 the several coats better than their colour. 

 The outer coat or theca folliculi was red ; the 

 second coat, or ovisac itself, chrome yellow ; 

 the now internal and newly formed coat was 

 milk-white. 



It remains to describe the cavity in the 

 interior of the follicle, which, though some- 

 times obliterated, is more frequently found still 

 existing at the fourth month of utero-gesta- 

 tion. In the specimen represented in fig. 387. 

 the cavity measured 3'" in diameter and con- 

 tained a clear gelatinous fluid. In other cases 

 a cavity at this time no longer exists, but the 

 centre of the ovisac is occupied by a tough 

 white substance, whose origin has just been 

 explained. 



It will not be requisite to follow out minutely 

 the remaining changes which the Graafian fol- 

 licle undergoes. After the fourth or fifth month 

 of pregnancy a certain diminution in size be- 

 gins to be perceptible. The walls of the cavity 



nplete obliteration approaches; but through 

 the subsequent changes of the follicle the 



approach nearer to each other, and the white 

 lining becomes thinner, and begins to be folded 

 into plaits which, radiating outwardly, are seen 

 intermingling with the yellow colour of the 

 proper ovisac (fig. 389.). The outer boundary 

 of the follicle also now presents an irregular 

 and somewhat angular and occasionally an 

 oval outline. These changes proceed with 

 much variation in different subjects ; but 

 usually at the time of delivery the ovisac, 

 though still yellow, has lost much of its 

 brightness, and the cavity, if it had existed, is 

 replaced by a solid white stellate cicatrix (fig. 

 389.) caused by the folding of the white lining 



Fig. 389. 



Graafian follicle two days after mature delivery. The 

 white lining of the cavity (c,fig. 387.) is here folded 

 into a stellate figure. It is surrounded by the dar- 

 ker yellow ovisac (corpus Inteum'), whose outline is 

 become angular. (After Montgomery.) 



membrane which bounded the ovisac on its 

 inner surface. That the yellow coat is still 

 vascular at this time is proved by the fact 

 mentioned in the preceding page. 



In proportion as the entire generative or- 

 gans subside into a quiescent state, so the re- 

 maining changes in the ovary take place more 

 rapidly. The yellow colour of the ovisac 

 passes into a paler hue, and at last into white. 

 The radiating cicatrix may still be traced for 

 some time longer, until, at the end of four or 

 five months after delivery, every appearance of 

 this structure has ceased to be discernible. 



Certain physiological questions intimately 

 connected with the foregoing history of the 

 development and involution of the ovarian fol- 

 licle may now be briefly considered. And first 

 it may be asked 



Does the discharge of ova from the ovary take 

 place independently of sexual intercourse, or of 

 any kind of infiuencefrom the male ? 



This question has long ceased to be agitated 

 with reference to animals lower in the scale 

 than the Mammalia. It need, therefore, now 

 only be considered in its relation to the latter, 

 including Man. And since many have recently 

 undertaken to prove that Man and the Mam- 

 malia constitute no exception to the general 

 rule that in all classes of the animal kingdom 

 which produce and emit ova the act of emis- 

 sion of ova is independent of the male, so, 

 whatever form the inquiry may now take, it 

 would naturally have for its chief object the 

 determination of the value of the evidence 

 upon which such an assertion has been based. 



Now, the facility with which the process of 

 ovulation may be observed in animals justifies 



