372 S. SAGUCHI 



the remaining portion of the cytoplasm is devoid of them, as 

 already noted by Policard ('12) in the liver cell, and as I have 

 also ascertained in the present investigation. 



Since a certain substance in the nucleus appears to be squeezed 

 out through the pores of the nuclear membrane, it must be ex- 

 pected that the primitive shape of mitochondria, at least in the 

 pancreas cell, will be filamentous, and that their ramification or 

 anastomosis, whether it may be a normal state or not, must have 

 been secondarily formed. And, in order that these filaments 

 maintain their form, it will be most essential that the organiza- 

 tion of the cytoplasm remain intact. If this organization is 

 disturbed in consequence of some external influences, either me- 

 chanical or chemical, the mitochondrial filaments can no longer 

 exist as such, but they become thick and short ; even break down 

 into granules or small vesicles; this is always met with in such 

 portions as have suffered mechanical injury or are imperfectly 

 fixed. 



There is no especially favorable position for the passing out 

 of the mitochondria; it can take place on either side of the nucleus. 



Now the question arises, from what nuclear substance do the 

 mitochondria originate? As already stated, there are three kinds 

 of substances which take part in the formation of the nuclear 

 network: one is the basichromatic substance and the others are 

 those forming nucleolus and nucleolar corpuscles. It has also 

 been concluded that the substance forming nucleolar corpuscles 

 and the cortex of the main-nucleolus is of the same nature. On 

 the other hand, the staining reactions of the mitochondria bear 

 a strong resemblance to those of the nucleolar corpuscles. This 

 strongly suggests that there may exist some genetic connection 

 between the two. In fact, it can often be seen that in the prepa- 

 rations fixed in Champy's and sublimate-formalin mixture and 

 stained with iron-haematoxylin, the nucleolar corpuscles are 

 drawn out into filaments which penetrate the nuclear membrane 

 and pass continuously into the mitochondrial filaments (figs. 

 53, 55). These observations have led me to the belief that the 

 mitochondrial substance is derived from the nucleolar corpuscles. 



