THE PANCREAS AS AN ENDOCRIN GLAND 707 



tions between acini and islands. The view that the islands are not inde- 

 pendent structures but develop from the acinar parenchyma, or that tran- 

 sition-forms exist between the two was held by many writers (Lewaschew, 

 Schmidt, Herxheimer, Karakascheff, Marchand, Benda, Gutmann, Hertel, 

 Koch, von Hansemann, Vincent, etc. ; while among anatomists Diamare, 

 Rennie, Massari, and De Witt have represented the "separate organ" view 

 of the islands. Karakascheff regarded the islands as having no* specific 

 significance for diabetes, but interpreted them as undeveloped portions of 

 the parenchyma, probably reserve organs. Von Hansemann strongly op- 

 posed the island view, and considered the islands to be variable pictures 

 representing non-secreting portions of the parenchyma and that the patho- 

 logic changes found in them are without significance and in no way influ- 

 ence the pancreatic secretion. Herxheimer took a middle point of view, 

 ascribing both an external and internal secretion to the pancreatic cells. 

 He believed that the islands develop from the acini, losing their external 

 secretion and taking on the internal function. Diabetes will be caused 

 by the loss of function of either component, but more rapidly by a loss 

 of that of the islands. This view was accepted by C. Koch, Lombroso, 

 Fahr and others. Fahr (1914), on trie ground of both experimental, 

 clinical and pathologic studies, concluded that neither the parenchyma 

 alone nor the islands alone regulated the sugar metabolism, and that 

 the pancreas possesses other functions than that of sugar regulation. 



Pathological Changes in Islands in Diabetes. Although Ulesko and 

 Laguesse had suggested that the islands of Langerhans might be concerned 

 in the internal function of the pancreas, it was Schafer (1895) who first 

 advanced the hypothesis that pathologic alterations of these structures are 

 responsible for diabetes. Schlesinger (1891), Dieckhoff (1894), Kasa- 

 hara (1896) had noted pathological changes in the islands in both dia- 

 betic and non-diabetic cases. Both Dieckhoff and Kasahara regarded 

 their findings as unfavorable to the island theory. Human diabetes 

 offered abundant pathologic material for purposes of study, and in the 

 early years of the new century there appeared the pathological observa- 

 tions of Opie, Ssobolew, Herzog, Weichselbaum and Stangl, Sauer- 

 beck, etc., which gave a stronger impetus to the island theory. Opie 

 studied thoroughly the pancreatic changes in five cases of diabetes ; in three 

 of these the cells of the islands showed a complete hyaline change, in the 

 other two cases the same condition but less marked. The acinous paren- 

 chyma was more or less altered in all. In non-diabetic cases the hyaline 

 change was not found. Opie's study (1901) did much to advance the island 

 theory. In the next year Wright and Joslin reported the finding of 

 the same hyaline change in three out of nine cases of diabetes. Ssobolew 

 found changes in the islands in fourteen out of sixteen cases of diabetes, 

 in the form of diminished number, complete absence, fatty degeneration, 

 pyknosis, and vacuolation with chromatolysis. In cases of advanced 



