250 PANCREATIC DIABETES 



chyma of the pancreas or with the ' * islands of Langerhans. ' ' 

 B. A. Kohn classes the islands of Langerhans along with 

 the parathyroids, the epithelial part of the hypophysis and 

 the cortex of the suprarenal glands, among glands without 

 duct or glandular lumen. 



Here it may be sufficient to state as a matter of reference 

 that U. Lombroso 6 after sifting the general material (col- 

 lected experiments with ligature of the ducts, artificially 

 induced atrophy of the parenchyma, pathological observa- 

 tions and studies in comparative anatomy), came to the 

 conclusion in a monograph upon the subject that both forms 

 of epithelial tissue of the pancreas, acini and islands, take 

 part in internal secretion. Swale Vincent, 7 in a recent 

 critical review, says : " Whatever may be found out in the 

 future in regard to the true function of the islands of 

 Langerhans, their essential anatomical relation with the 

 zymogenous tubules, the many transition forms met in all 

 vertebrate genera, and the transformation of acini into 

 islands and vice versa, apparently prove conclusively that 

 the islands are not sui generis, but that they are integral 

 constituents of the ordinary pancreatic tissue. Whether 

 the temporary transformation into insular tissue means a 

 particular specialization of function, our present evidence 

 does not indicate. ' ' In the author's personal opinion, it can 

 no longer honestly be doubted, in view of the recent investi- 

 gations of Weichselbaum (vide infra), that the anatomical 

 cause of diabetes is to be sought in lesions of the islets. 



Duodenal Diabetes. Some years ago Pfliiger took occa- 

 sion to use the observation that section of the intramesen- 

 teric nervous connections between the pancreas and 

 duodenum in the frog may under certain circumstances give 

 rise to a glycosuria, as a basis for calling into question the 

 existence of a pancreatic diabetes, and for substituting for 

 the latter a "duodenal diabetes/' The whole discussion 



6 U. Lombroso, Ergebn. d. Physiol., 9, 1-89, 1910. 



7 Swale Vincent, Ergebn. d. Physiol., 9, 489-495, 1910. 



