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CHAP. VIII. 



THE FUNCTION OF THE INTESTINES. 



"THE intestinal tube, over which the omentum is extended, and 

 which receives the chyme to elaborate it further and separate 

 the chyle from the faeces, is divided into two principal portions 

 the small and large intestines, of whose functions we shall speak 

 separately. 



" The small a intestines are again divided into three : the duo- 

 denum, jejunum, and ileum. 



The first is named from its usual length. 



" The second from generally appearing collapsed and empty. 



" The third from its convolutions : it is the longest of the three, 

 fuller, and, as it were, inflated, and sometimes resembling the 

 large intestines by the appearance of bullae. 



" The coats of the small intestines correspond with those of 

 the stomach. 



" The external is derived from the mesentery. 



" The muscular consists of two orders of fibres : the one lon- 

 gitudinal, interrupted, external, and found especially about the 

 part opposite the mesentery ; the other, annular and falciform, 

 possessing the power of narrowing the canal, while the former 

 shortens it. Upon both depends the very great and permanent 

 irritability of the intestines, formerly mentioned. 



" The nervous coat is condensed cellular membrane, easily 

 reduced by handling, or more particularly by inflation, into a 

 spumous tela b ; in it the intestinal blood-vessels, which arise from 

 the mesenteric 6 , are distributed in a beautifully arborescent 



a " Chr. Bernh. Albinus, Specimen anat. exhibens novam tenuium hominis 

 intestinor. descripiionem. LB. 1724. 8vo." 



b B. S. Albinus, Annotat. Academ. L. ii. tab. iv. fig. 1, 2." 

 " Eustachius, tab. xxvii. fig. 2. 4." 

 I 3 



