80 



Dr. J. Homans. The Relation of the [Oct. 1, 



a result of a post-mortem change peculiar to the guinea-pig, and which he 

 holds to be the same cells described as a transition form by Mankowski. At 

 first I was inclined to disagree with Bensley, and to consider the cell a 

 result of exhaustion rather than of a 'post-mortem process, for while I find 

 them abundant in exhausted glands, I have rarely seen one in a normal 

 organ. It seems to me, however, that as the circulation in animals subjected 

 to secretin stimulation becomes in the last half-hour very poor, and as their 

 temperature becomes considerably subnormal, the change may be partly 

 ante-mortem degeneration. Bensley's evidence that such cells can be pro- 

 duced as a result of post-mortem changes is very complete. That they are 

 produced by exhaustion is suggested by my preparations, but not proven. 

 Moreover, they have not been noted in the dog. In any case they furnish 

 the only suggestion of a possible transition of acinous to islet cells which I 

 have been able to find in the exhausted pancreas of the guinea-pig. 



Demonstration of Islets and Ducts by Vital Stains. 



I have made, perhaps, half-a-dozen injections of neutral red, pyronin, and 

 methylene blue, according to Bensley's method, and I can only say here that 

 the results fully bear out Bensley's contention that the islets have a distinct 

 staining reaction of their own. In the best preparations, the individual cells 

 can be distinguished, and, when the neutral red injection is combined with 

 pyronin, the relation of the islets to the ducts is quite obvious. Though I 

 have only made one attempt to demonstrate the islets in the exhausted 

 gland, the clearness of outline, size, and number of the islets was quite the 

 same as in the resting gland. For a full account of this technique and its 

 results in exhaustion and starvation, the reader is referred to Bensley's work. 



Nearly Complete Removal of the Pancreas in the Dog. 



The choice of the duodenal end of the pancreas as the part to be studied 

 was made with the full knowledge that the number of islets left would be 

 comparatively small. It was thought, however, that if an amount of this 

 pancreatic tissue could be left, such as would barely support life, a better 

 idea of the relation between acinous and islet tissue could be gained than by 

 the use of the splenic end, in which the islets are known to be much more 

 abundant. Although these experiments were planned primarily for this 

 purpose, the importance of the relation of the histological changes to the 

 carbohydrate metabolism made it necessary to observe the general condition 

 of the animals, and especially the amount of sugar appearing in the urine. 

 Accordingly, a brief protocol of each experiment is given, with a summary of 

 the histological findings at its termination. The observations are arranged 



