394 INTERNAL SECRETIONS OF PANCREAS AND SPLEEN. 



vestigators "found scattered through the organ glomerular 

 structures composed of dilated and tortuous capillaries, and 

 showed that these glomeruli correspond to the cell-groups 

 which Langerhans described. The islands are penetrated by 

 numerous wide, tortuous capillaries, which lie between cells, 

 forming irregular, anastomosing columns. Material injected 

 into the duct of the gland does not penetrate the islands." 

 The view that the islands of Langerhans furnish an internal 

 secretion is indirectly sustained, and the histological topography 

 outlined seems to furnish a clue to the mechanism involved: 

 i.e., the existence of two sets of glands capable of yielding similar 

 products, but adjusted individually, as regards distribution, to the 

 needs of two systems: the digestive system and the circulatory 

 system. 



To develop this proposition and that on page 379, we 

 will employ the excellent paper of E. L. Opie, 23 in which the 

 entire subject is not only reviewed, but also greatly elucidated 

 through personal investigations. The quotations from his 

 article will be limited, however, to the features bearing directly 

 or indirectly upon the question in point, as given in the above 

 italicized lines: 



"Schafer and Diamare think that the vascular islets prob- 

 ably furnish an internal secretion. The only evidence in sup- 

 port of this suggestion is contained in the short preliminary 

 notice of Ssobolew. He states that after feeding animals on 

 carbohydrates the cells of the islands become more granular. 

 After ligating the duct of Wirsung in dogs, the islands of 

 Langerhans, he finds, are not involved in the sclerotic process 

 which follows. He thinks that this fact explains the absence 

 of glycosuria after ligation of the pancreatic ducts. In human 

 cases I had observed after duct obstruction similar resistance 

 of the islands to the consequent inflammation. In pancreases 

 of two diabetics Ssobolew was unable to discover islands of 

 Langerhans. 



"In the human pancreas the islands were found to be more 

 numerous in the splenic end, or tail, than elsewhere. To 

 obtain a numerical statement of their relative abundance, their 



E. L. Opie: Loc. cit. 



