THE PANCREAS 47 



merits, and his results are carefully tabulated. He gives, 

 moreover, a careful account of the anatomy of the pancreas 

 in the pigeon. He states his conclusions as follows : " Chez 

 les animaux soumis a Finanition pendant quelques jours, le 

 nombre des ilots double presque, pour retomber a son taux 

 normal chez les pigeons renourris." " Nos observations, 

 completant . et elargissant celles de Swale Vincent et Thomp- 

 son, nous paraissent fournir une preuve experimentale tres 

 demonstrative du balancement." 



The results of recent investigations have not been very 

 concordant. M. Labbe and P. Thaon have reported an in- 

 crease in amount of islet tissue in guinea-pigs when fed on 

 animal food. This result may possibly be attributed to inani- 

 tion. 



Bensley, as the result of very painstaking work, finds 

 himself unable to agree with Vincent and Thompson. He has 

 used Lane's methods for the study of the cell granules and has 

 adopted the classification into A and B cells, according as 

 the granules are fixed respectively by alcoholic or watery 

 solutions. In order to test the question as to alterations in 

 islet tissue under different conditions, this author employed 

 the neutral red method for staining the islets and for their 

 enumeration. He has taken no account of the size of the 

 islets. He believes that the structures in question are con- 

 stant and do not change under different physiological 

 conditions. 



Von Hansemann confesses that he has been forced to change 

 his opinion as to the significance of the islets of Langerhans. 

 He now regards them as varieties of the parenchyma of the 

 organ and not as separate structures. He finds that in dia- 

 betes the changes in the islets correspond exactly to those in 

 the rest of the organ. 



Pratt and Murphy have observed that pancreatic tissue 

 implanted in the spleen and separated from its original vascular 

 and nervous connections can live and functionate for months. 

 A small nodule of pancreas composed of acini without demon- 

 strable islets prevented the development of diabetes. This 

 shows that the islets are not the only portions of the pancreas 

 which furnish an internal secretion. Other experiments of 

 the same nature and with similar results have been 

 recorded. 



