ON GENERATION. 497 



the conception or ovum ; nor has the ovum in these animals 

 at any time a connexion with the uterus. 



From all of what precedes it is manifest that in both the 

 classes of viviparous animals alluded to, those, namely, that are 

 provided with carunculae or cotyledons, and those that want 

 them, and perhaps in viviparous animals generally, the foetus 

 in utero is not nourished otherwise than the chick in ovo ; the 

 nutritive matter, the albumen, being of the same identical kind 

 in all. As in the egg the terminations of the umbilical vessels 

 are in the white and yelk, so in the hind and doe, and other 

 animals furnished with uterine cotyledons like them, the final 

 distributions of the umbilical vessels are sent to the humours 

 that are included within the conception or ovum, and to the 

 albumen that is stored in the cotyledons, or cup-like cavities of 

 the carunculae, where they open and end. And this is further 

 obvious from the fact of the extremities of the umbilical vessels, 

 when they are drawn out of the afore-mentioned mucor, looking 

 completely white ; a certain proof that they absorb this mu- 

 cilage liquefied only, and not blood. The same arrangement 

 may very readily be observed to obtain in the egg. 



The human placenta is rendered uneven on its convex surface, 

 and where it adheres to the uterus, by a number of tuberous 

 projections, and it seems indeed to adhere to the uterus by 

 means of these ; it is not consequently attached at every point, 

 but at those places only where the vessels pierce it in search of 

 nourishment, and at those where, in consequence of this ar- 

 rangement, an appearance as if of vessels broken short off is 

 perceived. But whether the extremities of these vessels suck 

 up blood from the uterus, or rather a certain concocted matter 

 of the nature of albumen, as I have described the thing in the 

 hind and doe, I have not yet ascertained. 



Finally, that the truth just announced may be still more 

 fully confirmed, it is found that by compressing the uterine 

 caruncles between the fingers, about a spoonful of the nutritive 

 fluid in question may be obtained from each of them, as from a 

 nipple, unmixed with blood, which is not obtained even with 

 forcible pressure. Moreover, the caruncle thus milked and 

 emptied, like a compressed sponge, contracts and becomes 

 flaccid, and is seen to be pierced with a great number of holes. 

 From everything, therefore, it appears that these caruncles are 



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