32 S. SAGUCHI 



dria undergo a definite change and there is formed a substance 

 which no longer exhibits the specific mitochondrial reaction, but 

 becomes impregnated by the Cajal method. It will be seen 

 from a comparison of the preparations that the above-mentioned 

 bodies are in full accord not only in position, but also in shape, 

 with the clear spaces or vacuoles produced by the liquefaction 

 of mitochondria, so that it is conceivable that the former is only 

 the positive figure of the latter. The corpuscles gradually dis- 

 appear from the cell. From the fact that they show a tendency 

 to proceed from the basal part of the cell toward the lumen, 

 and that they are often gathered near the latter, it is presumable 

 that they become in part, at least, extruded into the lumen. 



Second stage. A remarkable phenomenon of this stage is the 

 passing out of a certain intranuclear constituent. In the prepa- 

 rations fixed in osmic mixtures, especially in sublimate-osmic- 

 chromic acid, or in Zenker's mixture, and stained with iron- 

 hematoxyhn or acid fuchsin, there can easily be found nuclei 

 from which a deeply stained substance passes out in the form of 

 delicate, tortuous filaments or of minute granules (figs. 10, 11). 

 These at first are accumulated around the nucleus, but gradually 

 extend over the whole cytoplasm, and are finally so densely 

 packed together that the individual filaments are no longer 

 visible, the cytoplasm exhibiting rather a granular appearance 

 (fig. 13). These granules or filaments are nothing else than what 

 we have designated specific granules and the cell in question now 

 becomes a cell (fig. 14). 



The nucleus maintains its original spherical or polygonal form 

 and the meshes of the nuclear net become closer. The most 

 striking feature in this stage consists in the decrease in size and 

 volume of the nucleolus and nucleolar corpuscles, which may 

 perhaps be correlated with the passing out of the filaments or 

 granules. I am of the opinion that the specific granules of the 

 islet cell are derived from the nucleolar substance. The nucleo- 

 lus passes out of the nucleus not only in the mode described 

 above, but also in the form of larger spherical droplets or cor- 

 puscles formed by its constriction as is seen in figure 15. 



