On the Relations between the „Islets of Langerhans" etc. 101 



Fig. 5. From the splenic end of the pancreas of a dog which had undergone inanition 

 for some days. There is a very marked increase in the proportion of 

 islet tissue. Corrosive sublimate, haematoxylin and eosin. Cam. lue. Same 

 magnification as figs. 3 and 4. Reduced to ^/g of the original size. 



Fig. 6. Section of the pancreas of the ox (region doubtful) showing a leptochrome 

 islet and a bathychrome islet in close contiguity. The bathychrome islet 

 consists mostly of a syncytium, but in the lower part a few of the cell 

 outlines can be faintly seen. Compare this with figs. 7, 8, 12 and 13. 

 Fixed in Flemming's fluid, stained with iron-haematoxylin. As seen 

 under a magnification of 480 diameters. Cam. lue. Reduced to ^/g of 

 the original size. (See appendix.) 



Fig. 7. From the splenic end of the pancreas of a normal pigeon. The section 

 shows two large leptochrome islets and irregular columns of bathychrome 

 tissue. In this last tissue the cell outlines can be seen with extreme 

 difficulty, if at all, and the structure is continuous in some regions with 

 a mass of true syncytial form as shown in fig. 8. Corrosive sublimate, 

 haematoxylin and eosin. As seen under a magnification of 400 diameters. 

 Cam lue. Reduced to ^/3 of the original size. 



Fig. 8. Portion of zymogenous tissue and bathychrome syncytium from the splenic 

 end of the pancreas of a normal pigeon. In the bathychrome portion are seen 

 occasional red blood corpuscles and also the curious highly refractive cells 

 described in the text. Fixed in corrosive sublimate, stained with haema- 

 toxylin and eosin. x 400. Cam. lue. Reduced to ^/2 of the original size. 



Fig. 9. 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. Fixed in corrosive sublimate, and stained with haematoxylin 

 and eosin. Low power. Cam. lue. Reduced to '^/3 of the original size. 



Fig. 10. Splenic end of the pancreas of a pigeon after a few days inanition. The 

 increase in the amount of islet tissue is even more marked than in the 

 dog under similar circumstances. Compare this figure with the preceding. 

 Fixed and stained as in preceding specimen, and examined under the 

 same magnification. Cam. lue. Reduced to ^/3 of the original size. 



Fig. 11. Leptochrome islet from the same preparation as the preceding figure, 

 but not taken so near the splenic end. In the islet tissue are seen 

 columns of darker cells similar to those described by Diamare and others 

 in the islets of fishes. Same magnification and mode qf preparation as 

 the two preceding figures. Cam. lue. Reduced to ^/g of the original size. 



Fig. 12. Section from the splenic end of the pancreas of Kinosternon, showing a 

 leptochrome islet, the zymogenous tissue, and irregular columns of bathy- 

 chrome tissue in the left of the drawing. There are also some separated 

 portions — true „islets" — of this bathychrome tissue. To the right of 

 the sketch is a mass of adenoid tissue. Compare this with figure 7 from 

 the pigeon. Fixed in corrosive sublimate and stained with haematoxylin 

 and eosin. As seen under a magnification of 400 diameters. Cam. lue. 

 Reduced to ^/3 of the original size. 



Fig. 18. Pancreas of the frog, showing a large leptochrome islet, masses of bathy- 

 chrome tissue, and some zymogenous tissue. Corrosive sublimate, haema- 

 toxylin and eosin. x 400. Cam. lue. Reduced to ^/3. 



