44 INTERNAL SECRETION 



The present writer, as the result of investigations carried out 

 in conjunction with Mrs. Thompson, considers that the em- 

 bryological work of Laguesse and the experimental researches 

 of Dale are confirmed in all essential points. 



Fig. 9 represents an islet of Langerhans from the splenic 

 end of the pancreas of a normal dog, showing the " alveolar " 

 form of the islet tissue. The islet is seen to consist of solid, 

 branching columns of cells, for the most part two deep, sepa- 

 rated by wide capillary blood vessels. In some places the 

 zymogenous tissue shows transitions towards islet. Pig. 10 



. 



zym. 



FIG. 10. From the splenic end of the pancreas of a normal pigeon. The 

 section shows the islets and the zymogenous tissue. Compare this with 

 the next figure (Vincent and Thompson). (Drawn by Mrs. F. D. Thomp- 

 son.) Lettering same as for Fig. 9. 



is a section taken from the splenic end of the pancreas of a 

 normal pigeon. The section shows the islets and the zymo- 

 genous tissue. Compare this with Fig. 11, which shows the 

 splenic end of the pancreas of a pigeon after a few days' 

 inanition. The increase in the amount of islet tissue is very 

 striking. 



If a pancreas from an animal in inanition is examined, a 

 very remarkable increase in islet tissue is noted 1 (see Figs. 



1 It must be admitted that this does not occur with complete regularity, 

 '.bably depends upon the state of nutrition of the animal at th- time 

 ion is begun. 



