234 THE FCETUS. 



the womb, would lead us to suppose that there is a sort of contest 

 between the containing and the contained; however, nothing of the 

 sort takes place: the womb enlarges in consequence of the unfolding 

 of its fibres, and the affluxion of fluids into its vessels; the ovum 

 ceases to grow as soon as the organ that contains it ceases to de- 

 velop itself, and abortion may follow as a consequence thereof, but 

 without our being able to accuse a distending power which it by 

 no means possesses.* By rigidity of the uterus we ought to under- 

 stand a want of disposition in it to imbibe, to soften and distend, in 

 consequence of the accumulation of fluids in the insterstices of its 

 tissue, and not any resistance it may oppose to the swelling of tlie 

 ovum. 



602. Diseases of the ovum. The foundation of an abortion in a 

 majority of cases is laid in some peculiar disposition of the ovum 

 itself, and I am astonished that authors have paid so little attention 

 to this predisposing cause: like fruits that perish before they have 

 attained their full growth, and separate and fall at the slightest shake 

 of the branch on which they grow, so the embryo or the foetus in ani- 

 mals must become detached and soon afterwards expelled from the 

 womb when it has ceased to live. 



603. The alterations capable of bringing about the death of the 

 foBtus are extremely numerous, and so much the more so, in pro- 

 portion as the pregnancy is advanced. Since I began to pay regu- 

 lar attention to the subject of embryology, I have carefully observed 



* M. Velpeau asserts here that the growth of the womb depends upon the af- 

 fluxion of fluids into its vessels, and denies virtually, that the growth of the ovum 

 is the cause of that of the uterus. I do not pretend to know by what means the 

 liquor amnii is formed; but it is evident that the development of the foetus, and the 

 increase in quantity of the liquor of the amnios are the causes of the enlargement 

 of the organ that contains them; that that organ enlarges because of their en- 

 largement; and that it ceases to augment its capacity when they cease to increase 

 in bulk. 



The womb contracts soon after the rupture of the ovum and discharge of the 

 waters. This contraction takes place at any period of pregnancy when the wa- 

 ters are broken — is not this evidence enough to show, or rather prove that the 

 womb depends for its increase, not upon a power inherent in its own tissues, but 

 upon an antagonist force, to wit, the force which augments the bulk of the child, 

 while it at the same time distends the membranes more and more by dailyaddi- 

 tions to the stock of liquor of the amnios? 



I do not agree with M. Velpeau in the sentiment which he has expressed. I 

 prefer to regard the ovum as an independent existence; which, like a parasite, 

 draws its materials of subsistence from the surfaces to which it may be attached, 

 and which compels those surfaces to augment pari passu with its own necessities 

 as regards space, and surface for absorption. For an expression of my opinion 

 on this subject see the Philad. Pract. of Mid. p. 104. — M. 



