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Life and Health 





FIG. 60. Diagrammatic Scheme of a Trans- 

 verse Section of the Small Intestine. 



(In the figure on the left are seen the artery and vein 

 of a villus. In the right figure are represented 

 the central chyle vessel of villus, with plexus of 

 lymph vessels at the base. The mucous, sub- 

 mucous, muscular, and serous coats are indicated 

 at the base of the right-hand figure. The epi- 

 thelium of each villus is well shown.) 



have not only a very 

 large area of absorb- 

 ing surface, but also 

 structures especially 

 adapted to do this 

 work. It is a most 

 active and compli- 

 cated process. 

 **185. The Work 

 done by the Lacteals. 

 We have learned 

 that the mucous 

 lining of the small 

 intestines is crowded 

 with millions of little 

 appendages called 

 villi, meaning "tufts 

 of hair." These are 

 only about one-thir- 

 tieth of an inch long, 

 and a dime will cover 

 more than five hun- 

 dred of them. Each 

 villus contains a loop 

 of blood vessels, and 

 a special kind of lym- 

 phatics, called the 

 lacteals, so named 

 from the Latin word 

 lac, because of the 

 milky appearance 

 of the fluid they 

 contain. 



