HISTOLOGY 



121 



and the mucigcn-coiitaining upper parts of the cells are distended. They are 

 especially numerous in the ileum. Some of the cells lining the bases of the 

 tubules contain acidophilic cytoplasmic granules above their nuclei. These 

 are the cells of Paneth, which become more conspicuous after several hours 

 of fasting and are most frequent in the jejunum. 



^ Villi 



Epithelium 



Lamina propria 



''^.'; 



••• • • • , - • 



Fig. :;6. 



Intestinal gland 



Muscularis mucosae 



Submucosa 



• Circular muscle 

 layer 



Longitudinal muscle 

 layer 



Serosa 



-Ileum, longitudinal section. (X200.) 



The lamina propria forms the center of each villus and tills the spaces 

 between the glands. It is composed of reticular tissue containing many 

 lymphocytes, some granular leukocytes (especially eosinophils), and plasma 

 cells. 



The muscularis mucosae is very delicate. The submucosa consists of 

 loose connective tissue. In the submucosa of the pyloric valve and extend- 

 ing for a few millimeters along the wall of the duodenum, coiled, tubulo- 

 alveolar mucous glands are present. These are the duodenal glands (of 

 Brunner) (Fig. 55). Although they are located in the submucosa, some 

 parts of the glands may be present in the mucosa. The glands are lined 



