THE UMBILICAL CORD. 569 



the means by wliich the nutrient matter is taken up, as by 

 rootlets, and distributed to the foetus. The veins of the 

 cord are marked at various places by knots or varices, resem- 

 bling vesicles filled with blood ; this is a contrivance of nature 

 to prevent the blood rushing too violently to the foetus. From 

 the number of these knots superstitious midwives are accus- 

 tomed to predict the number of the future offspring; and if 

 none can be seen at all they pronounce that the woman will be 

 ever after barren : they also absurdly prophesy by the distance 

 between the knots about the interval to take place between the 

 birth of each child, and also of its sex from their colour. 



A like arrangement of the umbilical vessels is found in 

 almost all foetuses furnished with a single placenta, as in the 

 dog, mouse, and others ; but in these the cord is shorter and 

 less convoluted. In the ox, sheep, red-deer, fallow-deer, hog, 

 and others, in which the nutrient material is not supplied from 

 one fleshy mass or placenta, but from several, the umbilical 

 vessels are distributed in a different manner. The branches and 

 extremities of these vessels are not only disseminated through 

 the fleshy substance, but still more and chiefly through the 

 membrane of the chorion itself by means of the most delicate 

 fibres; exactly in the same way as the vessels are distributed 

 in the human foetus, without the aid of the cord, before the 

 "conception" adheres to the uterus. .Hence it is plain that 

 the embryo does not derive all its nourishment from the pla- 

 centa, but receives a considerable portion of it from the fluid 

 contained in the chorion. 



As to the uses of the umbilical vessels, I cannot agree with 

 Fabricius, for he imagines that all the blood is supplied to the 

 foetus from the uterus by means of the veins, and that the 

 vital spirits are transmitted from the mother by the arteries. 

 He also asserts that no part of the foetus performs any common 

 function, but that each individual portion looks only to itself, how 

 it may be nourished, grow, and be preserved. In like manner, 

 because he has found no nerve in the umbilical cord, he refuses 

 to allow sensation or voluntary motion to the foetus. Just as 

 if the uterus or placenta of the mother were the heart or first 

 source whence these functions are derived to the foetus, and 

 whence heat flows in and is distributed through all its parts. 

 All these are manifest errors. For the human foetus, even 



