DIGESTIVE GLANDS. 



215 



cells are present. These are smaller and flatter 

 than the chief cells and occupy a central position of 

 many acini. They represent an invagination of the 

 neck of the acinus and are best understood by re- 

 ferring to Fig. 1 60. 



Areas of Langerhans.- These are oval cell masses 

 that measure 0.2 to 0.3 mm. They are found in the 

 lobules of the pancreas, always associated with the 

 connective tissue but having no connection with the 



Pancreatic duct. 



Acinus. 



Blood capil- 

 laries. 



Connective tissue. Area of Langerhans. 



Fig. 161. Section from an injected pancreas of the dog. 



pancreatic tubules. The areas are surrounded by a 

 rich supply of coarse capillary blood-vessels. The 

 individual cells are epithelioid, smaller than those 

 of the acini, arid finely granular. In many respects 

 they resemble the liver cells. It is believed that the 

 secretions from these cells is absorbed by the blood 

 and modifies the distribution and elimination of 

 sugar. The areas thus have a compensatory rela- 

 tion to the liver and may do in part the work of that 

 organ. A marked disturbance in these areas has 



