360 OF CONCEPTION 



chord ; while the carbonised blood returning from the 

 foetus, through the umbilical arteries, being poured in 

 the same manner into the substance of the placenta, is 

 absorbed by the venous radicles of the uterine portion 

 of the placenta, and returned to the uterus. 



This account is supported by very careful but fruit- 

 less attempts to inject the umbilical by means of the 

 uterine vessels, and the uterine by means of the umbi- 

 lical ; or to tinge the bones of the foetus with red, by 

 giving madder to the mother during pregnancy. It is 

 also confirmed by the difference observable between 

 the blood of the mother and foetus. (E) 



576. During the progress of pregnancy, while the 

 foetus and secundines are increasing, the uterus of 

 course undergoes important changes, not only in size, 

 but in situation, figure, and especially in its texture, 

 which is considerably changed both with respect to its 

 blood-vessels and the intervening parenchyma, from 

 the constant and great congestion of fluids that occurs. 



In proportion as the uterus increases, the blood- 

 vessels from being tortuous and narrow become more 

 straight * and capacious, and the veins, near the ter- 

 mination of pregnancy, acquire so great a bulkf as 

 to have been taken for sinuses by some anatomists. 



The parenchyma becomes gradually more thin and 

 lax, especially in the part nearest the ovum, so that 

 although the gravid uterus is very thick, particularly 

 at its fundus, and in a living and healthy woman is 

 turgid with blood and replete with vital energy, never- 



* v. W. Hunter, dnat. Uteri Gravidi. tab. xvi. 



f- Ibid. tab. xviii. 



J v. B. S. Albinns, Axnotat. Acad. i. ii. tab. iii. fig. 2. 



