204 



ELEMENTS OF HISTOLOGY. [Chap, xxv, 



of the general surface, and their tissue is the same as 

 that of the mucosa i.e., adenoid tissue with the 

 addition of : (a) One or two central wide chyle (lymph) 

 vessels (see Fig. 120), their wall being a single layer 

 of endothelial plates, (b) Along these chyle vessels 

 are longitudinal bundles of non-striped muscular tissue, 

 extending from the base to the apex of the villus, 

 terminating in connection with the cells of the base- 

 ment membrane i.e., the subepithelial endothelium. 



(c) A network of 

 capillary blood- 

 vessels extending 

 over the whole of 

 the villus close to 

 the epithelium of 

 the surface (Fig. 

 119). This capil- 

 lary network de- 

 rives its blood 

 from an artery in 

 about the middle 

 or upper part of 

 the villus. Two ve- 

 nous vessels carry 

 away the blood 

 from the villus. 



The Lieberkiihii's crypts open between the bases of 

 the villi. 



At the sides of the villi of the small intestine, 

 and at the sides of the plicae villosae of the stomach 

 (see a former chapter), there exist amongst the epithe- 

 lium of the surface peculiar goblet-shaped groups of 

 epithelial cells, which, as Watney has shown, are due 

 to local multiplication of the epithelial cells. 



272. Lymph follicles occur singly in the submucosa, 

 and extend with their inner part or summit through 

 the muscularis mucosae into the mucosa to near the 



Fig. 119. From a Vertical Section through 

 the Small Intestine of Mouse; the Blood- 

 vessels are injected. 



The networks of the capillaries of the villi are 

 well shown. (Atlas.) 



