CHAPTER VI. 



THE METHOD OF DISCOVERING THE LYMPHATICS IN TURTLE AND 

 IN FISH, TOGETHER WITH A DESCRIPTION OF THOSE VESSELS 

 IN A HADDOCK. 



IN the foregoing chapter on the lymphatic system in a 

 turtle, I have made no mention of the manner of discovering 

 those vessels, because there is no difficulty in doing it ; for in 

 that animal the mesentery being very thin and transparent, 

 and the lacteals pretty large, they are more readily observed 

 than in any other animal ; thence it happened that I saw those 

 vessels in a turtle so long ago as 1763, which was before I dis- 

 covered them in birds and fish. 



But although it was an easy matter to see those vessels in 

 the turtle, yet it was far from being so in birds and fish ; as 

 the reader will readily believe, from their having been so often 

 sought for in vain by so many eminent anatomists (LXVI*), par- 

 ticularly of this age. I may add, that the discovery in birds did 

 not give me so much trouble as that in fish, though now, since I 

 have once seen them, I can more readily find them in fish than 

 in birds or quadrupeds. After seeing them in birds, and in 

 one of the amphibia, I was very desirous of determining whether 

 fish were or were not provided with those vessels. This I en- 

 deavoured to do in the same way that I had found them in 

 birds, that is, by tying up the mesenteries of live fish ; and for 

 this purpose I went frequently to the markets, and examined 

 several small ones. I likewise dissected some larger when 

 dead, but in vain. I next went to Brighthelmstone, where I 

 found kingston, or monk-fish, a species of skate. These being 

 very large, and having a lean mesentery, seemed well fitted to 

 my purpose, I opened two of them alive, tied up their mesen- 

 teric vessels, and put them again into the salt water ; and 



(LXVI*.) Thomas Bartholin, referred to in the Introduction, saw lac- 

 teal vessels in a fish. 



