STUDIES ON THE PANCREAS OF THE GUINEA PIG 



317 



TABLE 1— Continued 



occur, even in the oldest. Accordingly they must either have 

 disappeared, or have been transformed into cells of another type 

 or have been converted by mitosis or by accretion of new elements 

 into larger islets. The latter possibility is excluded by the fact 

 that the counts which become more and more accurate as the 

 pancreas increases in size show no increase in numbers in propor- 

 tion to the single islet cells of the pancreas of the new born. 

 Either of the other possibilities involves disappearance of islet 

 tissue. 



The evidence that new islets are being produced from time to 

 time will be given in detail in connection with the discussion of 



