256 OF THE FUNCTION 



intestines. To facilitate this, the extremity of the ileum 

 is lubricated very abundantly by mucus. 



414. The valve of the colon,* or, as it may deservedly 

 be termed after its discoverer, the valve of Fallopius,f 

 is a short process or continuation of the portion of the 

 ileum that penetrates into the cavity of the large in- 

 testine and is surrounded by it. Its external lips, while 

 a neighbouring fold of the large intestine at the same 

 time projects considerably, are composed, J not like 

 other similar folds, merely of the interior and ner- 

 vous coats, but of fibres from the muscular coat. Hence 

 it performs the double office of preventing the passage 



* Haller, De valvula coli. Getting. 1742. 4to. reprinted in his Oper. minor. 

 T. i. p. 580 sq. 



T. Mich. Riiderer, De valvula coli. Argent. 1768. 4to. 



t The various opinions respecting the discoverer of this reraarkahle valve 

 are well known. Haller's Element a. T. vii. P. 1. page 142, may be consulted 

 on this point. 



In the mean time I am certain that, long before the period at which its disco- 

 very is in general dated, it was accurately known to that immortal anatomist 

 Gabr. Fallopius. In our university library there is a manuscript of Fallopius, 

 containing, among other things, his anatomy of the monkey, in which is an ac- 

 count of the structure and use of the valve of the colon, delivered in a public 

 demonstration at Padua, Feb. 2. 1553. in the following words: " The use of 

 the ccBciim in the monkey, is to prevent the regurgitation of the food during 

 progression on all fours. This is proved by the circumstance of water or air t 

 throivn into the rectum, reaching the ccecum, but not passing- beyond the large 

 intestines. But, if impelled from above, it passes into them. The reason is 

 this, at the insertion of the ileum are two folds, which are compressed by in- 

 flation and repletion, as occurs in the heart, and prevent retrogression ; where- 

 fore, in man, clysters cannot pass and be rejected through the mouth, unless in 

 a weak and diseased state of the intestines." 



I A view of a recent and entire valve is exhibited by B. S. Albinus in his 

 Annotat. Academ, L. iii. tab. v. fig. 1. and overcharged by inflation and dry- 

 ing, in Santorini's Posthumous Tables, xiv. fig. 1, 2. 





