444 



THE ALIMENTARY CANAL. 



[CH. XXVII. 



tissue. Two or three tubes open into one duct, which forms about 

 a third of the whole length of the tube and opens on the surface. 

 The ducts are lined with columnar epithelium. Of the gland- 

 tube proper, i.e. the part of the gland below the duct, the upper 

 third is the neck and the rest the body. The neck is narrower 

 than the body, and is lined with coarsely granular polyhedral 



cells which are continuous with the 

 columnar cells of the duct. Between 

 these cells and the basement mem- 

 brane of the tubes, are large oval 

 or spherical cells, opaque or granular 

 in appearance, with clear oval nuclei, 

 bulging out the basement membrane ; 

 these cells are called parietal cells. 

 They do not form a continuous 

 layer. The body, which is broader 

 than the neck and terminates in a 

 blind extremity or fundus near the 

 muscularis mucosse, is lined by cells 

 continuous with the central cells of 

 the neck, but longer, more columnar 

 and more transparent. In this 

 part are a few parietal cells of the 

 same kind as in the neck (fig. 



373)- 



(6) Pyloric Glands. These glands 



(fig. 375) have much longer ducts 

 than the cardiac glands. Into each 

 duct two or three tubes open by 

 very short and narrow necks, and 

 the body of each tube is branched, 

 wavy, and convoluted. The lumen 

 is large. The ducts are lined with 



columnar epithelium, and the neck and body with shorter and 

 finely granular cubical cells, which correspond with the central 

 cells of the cardiac glands. As they approach the duodenum the 

 pyloric glands become larger, more convoluted and more deeply 

 situated. They are directly continuous with Brunner's glands 

 in the duodenum. 



Lymphatics. Lymphatic vessels surround the gland tubes to 

 a greater or less extent. Towards the fundus of the cardiac 

 glands are found masses of lymphoid tissue, which may appear as 

 distinct follicles, somewhat like the solitary glands of the small 

 intestine. 



Fig. 375. Section showing the pyloric 

 glands. ., free surface ; d, ducts 

 of pyloric glands ; n, neck of 

 same ; m, the gland alveoli ; 

 mm, muscularis mucosee. (Klein 

 and Noble Smith.) 



