1638 



HUMAN ANATOMY. 



layer of columnar cells directly continuous with those covering the villi. They differ 

 from the latter in being only about half so high (.018 mm. ) and in not presenting the 

 characteristic cuticular border. This last gradually disappears as the cells dip into 



Fig. 1387. 



^%^"^ "^4i />'^^ 



Xapillary 



Cuticular border 

 jithelium 







^<^ ^•'® o « 



<M§ff%'.^\ 





— Stroma of 

 mucosa 



Transverse section of single intestinal villus, showing relation of 

 epithelium, stroma, and vessels. X 356. 



Fig. 1388. 



Surface view of mucous membrane from 

 end of jejunum showing valvula; conni- 

 ventes. Stippled appearance is due to villi 

 covering folds. Natural size. 



the follicles to become the lining of the glands. Under low magnification the sur- 

 face of the small intestine presents numerous pits, the orifices of the glands, which 

 almost entirely fill the spaces between the bases of the villi ; with the exception of 



Fig. 1389. 



Submucous coat 



Villi 



Mucosa 



Submucosa 



rcular 

 uscle 



Longitudinal 

 muscle 



Longitudinal section of duodenum ; valvute coiiiii\entes cut across, showing relation of these folds to villi. X 15. 



the areas immediately over the lymph-nodules, where they are partially pushed aside, 

 these glands are present in all parts of the intestine. They, however, take no part in 

 absorption, never containing fatty particles during periods in which such substances 



