DISTRIBUTION OF BLOOD-VESSELS TO THE VILLI. 



85 



stitutes what is called a villus, the shape of which is conical, or perhaps 

 cylindrical. The villus may then be regarded as a process of mucous 

 membrane. 



Fig. 23 is a section of the wall of the ileum, 

 a being the villi ; b, glands of Lie- Structure of 

 berkuhn ; <?, muscular layer of mu- -the intestinal 

 cous membrane ; d, follicles of a Pey- T 

 er's patch ; 0, remainder of submucous tissue be- 

 neath them; y, circular muscles; g h, longitu- 

 dinal muscles. (Kolliker.) 

 fig. 24 represents the .distribution of blood- 

 vessels to the villi of the intestine of the mon- 



Fvj. 24. 



Section of wall of ileum magnified 

 50 diameters. 



Distribution of arteries and veins on villi of 

 monkey. 



key. The figure was drawn by the camera lucida, a a being the arteries, 

 b b the veins. 



The form of the villi differs in different regions of the intestine. In 

 the duodenum thev are less elevated, laminated, and broad- 



t - , T . t T -i --i Forms of villi. 



er, Fig. 25. In the jejunum, more projecting or cylmdroicl, 



Fig. 25. 



Fig. 20. 



Distribution of blood-vessels on the villi of the 

 duodenum. 



Distribution of blood-vctesels on the villi of the je- 

 junum. 



Fig. 26. In all cases, however, they are abundantly supplied with blood- 



