24 The Intestines. 



The small intestines commence at the stomach, 

 and in their course receive the several names 

 duodenum, jejunum, and ilium, the divisions being 

 purely imaginary. 



About five or six inches below the stomach are 

 the orifices which discharge the secretions of the 

 liver (bile) and pancreas (a fluid resembling saliva) . 

 Besides these, other special fluids are poured from 

 the walls (coats) throughout the length of the canal. 



The walls are strong and provided with mus- 

 cular fibres, as the gullet and stomach, to pro- 

 duce the necessary contractions (vermicular or 

 worm-like) in order to subject the contents 

 (ingesta) to the action of the various fluids, as 

 well as cause it to pass onwards. 



Throughout the inner surfaces of the small 

 intestines a number of peculiar vessels are seen 

 to enter. Their office is to abstract the nutri- 

 tious elements of the food, which after meeting 

 with the various secretions in the tube, assumes 

 a whitish creamy consistence, and is termed 

 chyle. The vessels here spoken of are termed 

 lacteals. They communicate with other vessels 

 and glands. In them the chyle as it passes on- 

 wards alters its constitution, and by successive 

 stages assumes the character of the blood with 

 which it is afterwards mixed. This constitutes 

 the process of assimilation. 



The small intestines are from fifty to sixty feet 

 in length, and will accommodate from eight to 

 elevens gallons of fluid. 



