THE GLAXDS OF LIEBERKUHN 



293 



region where these peculiar cells occur and as the granule cells 

 are never displaced toward the surface, it seems more probable 

 that, as also in the gastric glands, the indifferent genetic cells of 

 the neck of the tubule develop on the one hand the superficial 

 goblet and columnar cells which clothe the villi, and, on the other 

 hand, the true secreting cells in the f undus of the glands of Lie- 

 berkiihn. 



FIG. 239. FROM A LONGITUDE 



'ION OF THE PYLOBIO VALVE" OF MAN. 



a, glands of Brunner; 5, pyloric mucosa; c-c, muscularis mucosae; d, inner layer of 

 the muscular coat; , outer layer of the muscular coat: /, muscular thickening at the 

 pylorus; g, common bile duct. Hematein and eosin. Photo, x. 48. 



The granule cells of Paneth * are confined to the extreme tip 

 or blind extremity of the f undus of .the mucous crypts. They are 

 pyramidal or low columnar cells whose spheroidal nuclei are situ- 

 ated close to the basement membrane. Their cytoplasm presents 

 a delicate reticulum which is filled with coarse granules which in 



* Arch. f. mik. Anat., 1888. 



