well as the coverings of the foetus and the foetus itself, a product of the 

 act of generation. Though it adheres commonly to the fundus of the 

 uterus, it may adhere to any other point of its parietes; sometimes, jeven, 

 it is placed on its orifice, a circumstance which always makes delivery 

 difficult. The side by which it is united to the internal face of the uterus, 

 is uneven, covered with mamillary projections (cotyledons^) which are 

 sunk in corresponding ceils of the parietes of the uterus, the internal 

 surface of which, loses, as it developes itself, the smoothness which it 

 had while empty, as it is furrowed with depressions destined to receive 

 theplacenta, and studded with projections which penetrate into the cells 

 of the latter. 



The uterine arteries, and perhaps likewise the absorbents which are so 

 large and numerous in the gravid uterus, that Cruickshank,who succeeded 

 in injecting them, compares them to quills, thrown out, on the surface of 

 the placenta, and within its spongy tissue, the arterial blood of the mo- 

 ther; according to some, these vessels exhale only the serous part of the 

 blood, and according te others, a chylous, lymphatic, whitish, or milky 

 substance*. These fluids, effused within the cells of the placenta, are 

 absorbed by the numerous minute divisions of the umbilical vein, which 

 by thier union form the trunk of this vessel. 



The umbilical vein, arising from the interior of the placenta, by nu- 

 merous branches, detaches itself from it, and goes towards the umbilicus 

 of the child, enters his body, at that aperture, ascends, in a fold of the 

 peritoneum, behind the recti muscles, to the anterior extremity of the 

 sulcus of the liver, goes along the anterior of this fissure, sending a num- 

 ber of branches to the lobes of that viscus, especially to the left lobe. 

 On reaching the right extremity of the transverse fissure, where this last 

 meets the anterio-posterior, it unites, in part, with the sinus of the vena 

 portse hepatica, while .the remainder of the vessel, called ductus venosus, 



* A German physician, SCHKEGER has suggested a very ingenious opinion on the mode 

 of circulation, between the mother and child. He believes that the uterine arteries 

 pour out nothing but serum, into the cells of the placenta. This serum is absorbed by 

 the lymphatics, whose existence 'he infers from analogy, in this organ and in the um- 

 bilical cord, in which, however, no one has yet succeeded in injecting them. These 

 vessels convey it to the thoracic duct, \Vhence it is poured into the left subclavian vein, 

 and at -last, reaches the heart, which sends it along the aorta. It returns to the placenta 

 by the umbilical arteries, after being converted into blood, by the actions of the organs 

 of the foetus. This serosity, after undergoing the process of sanguification, returns 

 to the foetus by the umbilical vein, and following the well-known course of the foetal 

 circulation, is subservient to the nourishment of its organs. The branches of the um- 

 bilical arteries and veins, ramified in the placenta and communicating together in this 

 spongy tissue, reject through their lateral pores that which can rto longer serve to the 

 maintenance of the foetus. This residue of nutrition, deposited in the cells of the pla- 

 centa, is absorbed by the lymphatics of the uterus, which carry it back into the mass of 

 the fluids of the mother. Not to mention the impossibility of demonstrating the pre- 

 sence of the lymphatics, in the placenta, or in the umbilical cord, Schreger's hypothesis 

 ia attended with two objections. How does the nutritious fluid, coming from the mo- 

 ther and se \ along the aorta of the fcetus to every part of its body, return to the pla- 

 centa, to be brought back again by the umbilical vein ? Absorption scarcely goes on in 

 the foetus; the unctuous substance with which the body of the fcetus is covered, pre- 

 vents that function from taking place on the surface of the body. It goes on with very 

 little more activity, within the body: the excrementitious secretions scarcely exist before 

 birth ; whatever is conveyed to the foetus is employed in the developcment of its or- 

 gans ; hence its growth is so rapid. Author's Note. 



See the remark on the function of the* placenta in the Note (Note II.) in the AP- 



