400 



THE DIGESTIVE SYSTEM 



FIG. 373. SECTION OF AN ACINUS FROM THE GUINEA-PIG'S PANCREAS, SHOWING THE 

 BASAL MITOCHONDRIAL CONTENT AND THE CENTRAL ZYMOGEN GRANULES. 



Bensley's mitochondrial technic. X 1200 (After Bensley, Am. Jour. Anat., 12, 3, 

 1911.) 



The islet cells are arranged in irregular cords, frequently 

 only two_ cells deepT^ymg in the meshesof capilliform sinusoids, from 

 which they appear to be separated" by little more than the endothelial 



FIG. 374. INTERCALARY DUCT WITH BRANCHES, FROM PANCREAS OF GUINEA-PIG, 

 SHOWING HIGHLY BRANCHED TUBULES CONNECTED WITH THE DUCT AND WITH 

 AN ISLET. 



Intravitam staining with pyronin and neutral red. X 50. (Bensley, Amer. 

 Jour. Anat., 12, 3, 1911.) 



wall. The cells are divisible into two distinct, apparently independent 

 types, on the basis of their granular content (Lane, Amer. Jour. Anat., 

 7, 3, 1907). The *A ? and 'B' granules differ morphologically and micro- 



