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from the yelk always so terminate. In the selfsame way, therefore, as the chick is nourished from a nutriment, (viz. the albumen and vitellus,) previously prepared, even so does it continue to be nourished through the whole course of its independent existence. And the same thing, as I have elsewhere shown, is common to all embryos whatsoever : the nourishment mingled with the blood, is transmitted through their veins to the heart, whence moving on by the arteries, it is carried to every part of the body. The foetus when born, when thrown upon its own resources, and no longer imme- diately nourished by the mother, makes use of its stomach and intestines just as the chick makes use of the contents of the egg, and vegetables make use of the ground whence they derive concocted nutriment. For even as the chick at the commencement obtained its nourishment from the egg, by means of the umbilical vessels (arteries and veins) and the circulation of the blood, so does it subsequently, and when it has escaped from the shell, receive nourishment by the mesen- teric veins ; so that in either way the chyle passes through the same channels, and takes its route by the same path through the liver. Nor do I see any reason why the route by which the chyle is carried in one animal should not be that by which it is carried in all animals whatsoever; nor indeed, if a cir- culation of the blood be necessary in this matter, as it really is, that there is any need for inventing another way.
I must say that I greatly prize the industry of the learned Pecquet, and make much of the receptacle which he has dis- covered ; still it does not present itself to me as of such im- portance as to force me from the opinion I have already given ; for I have myself found several receptacles of milk in young animals ; and in the human embryo I have found the thymus so distended with milk, that suspicions of an imposthume were at first sight excited, and I was disposed to believe that the lungs were in a state of suppuration, for the mass of the thymus looked actually larger than the lungs themselves. Frequently, too, I have found a quantity of milk in the nipples of new-born infants, as also in the breasts of young men who were very lusty. I have also met with a receptacle full of milk in the body of a fat and large deer, in the situation
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