VOL. LXXXVI.] PHILOSOPHICAL TRANSACTIONS. (J75 



tained. A number of lacteals having entered one of these bags, were observed 

 to communicate with each other, then again to separate, and form other vessels, 

 which went out of the bag. It was some time before the quicksilver passed through 

 the plexus of vessels contained in the first bag ; but after having pervaded it, it 

 passed on to a '2d bag, in which was concealed a similar plexus of lacteals. The 

 quicksilver permeated these last vessels with much greater facility than it did the 

 former, and quickly ran out of the large lacteals which were divided at the origin 

 of the mesentery. Besides those absorbents which passed through the bags in 

 the manner described, there were great numbers of others, which terminated by 

 open orifices in every part of them. When quicksilver was poured into any of 

 the lacteals, which were found near the sides of the bags, it immediately ran in 

 a stream into their cavities. I introduced about a dozen bristles through as 

 many lacteals, into different parts of 2 of these bags. These were doubtless 

 few, in comparison to the whole number which terminated in them, but as the 

 mesentery was fat, and the vessels small, more could not easily be passed. 



I afterwards stuffed 2 of the bags with horse-hair, dried them, and preserved 

 them as an anatomical preparation. In this state great numbers of arteries and 

 veins, but chiefly of the former vessels, are seen terminating on their inside, in 

 the same indistinct manner as the foramina Thebesii appear when the cavities of 

 the heart are laid open : the bristles also render visible the termination of a cer- 

 tain number of lacteals. I examined the sides of these bags, which were mode- 

 rately thick and firm ; but I did not see any thing which, from its appearance, I 

 could call a muscular structure. 



Prom the circumstances that have been related, it appears, that in the whale 

 there are 1 ways by which the chyle can pass from the intestines into the tho- 

 racic duct ; one of these is through those lacteals which pour the absorbed chyle 

 into bags, in which it receives an addition of animal fluids. The other passage 

 for the chyle is through those lacteals which form a plexus on the inside of the 

 bags ; through these vessels it passes with some difficulty, on account of their 

 communications with each other ; and it is conveyed by them to the thoracic 

 duct, in the same state that it was when first imbibed from the intestines. The 

 lacteals, which pour the chyle into the bags, are similar to those which terminate 

 in the cells of the mesenteric glands of other animals: there is also an analogy 

 between the distribution of the lacteals on the inside of these bags, and that 

 which we sometimes observe on the outside of the lymphatic glands in general. 

 In either case, a certain number of the vasa inferentia, as they are termed, 

 communicate with each other, and with other vessels, named vasa efterentia. 



By this communication, the progress of the fluids contained in these vessels is 

 in some degree checked; which impediment increases the effusion into the ca- 

 vities of the gland made by the other lacteals: but should these cavities be ob- 



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