Hatai, Spinal Ganglion Cells. 37 



there is a circulation of the Nissl granules between the nucleus 

 and cytoplasm. In the general description of the nerve cell, 

 my results agree with those of Holmgren in the following 

 points : (i) the rays of the attraction sphere run into the nu- 

 cleus where they become continuous with nuclear network, (2) 

 the Nissl granules migrate from the nucleus either as minute 

 granules or accessory nucleoli, (3) the nuclear membrane be- 

 comes perforated along the surface which turns toward the 

 cytoplasmic processes. However, I was tmable to see the 

 basophile granules either within the centrosphere or along the 

 astral rays in the cytoplasm. Therefore, Holmgren's hypo- 

 thesis of the return of the formed Nissl granules into the nu- 

 cleus is not supported by the appearances in the nerve cells of 

 the white rat. My own observation suggests that the Nissl 

 granules which have migrated from the nucleus are utilized for 

 the maintainance of the cell body and what remains of them 

 after they are broken down, together with fresh material, is 

 taken into the nucleus by means of the pseudopodia-like pro- 

 cesses. For the above view, the following evidence may be 

 presented : 



(i) The pseudopodia-like processes of the nucleus are di- 

 rected towards the central corpuscles of the centrosome. Ac- 

 cording to KoRSCHELT ('91), HoFFMANN ('03) and others the 

 pseudopodia-like processes arc to be regarded as organs taking 

 up nourishment from the surrounding cytoplasm. 



(2) In them, as well as in their vicinity, basophile granules 

 are abundant. 



(3) Within the nucleus, the astral rays are surrounded by, 

 or have attached to them, a large number of basophile granules. 



(4) Positive proof of the presence of iron and phosphorus 

 was obtained in the granules along the rays, as well as 

 within the centrosphere, although they did not give with 

 Heidenhain's iron-haematoxylin nor with the tricolor methods 

 reactions similar to that produced in the Nissl granules. This 

 proves that the substances necessary for the formation of the 

 nuclein bodies (Nissl granules) are present in the centrosphere 

 as well as in its rays, in a peculiar form. 



