EFFECT OF OVER-ACTIVITY ON SYNAPSE 259 



The neuroglia nucleus is surrounded by a variously wide bor- 

 der of protoplasm, which latter sends protoplasmatic processes 

 in different directions. The process itself ramifies and becomes 

 more and more delicate, until it passes into the beams of the Golgi 

 net or becomes attached to the wall of a capillary. This picture 

 could very clearly be observed in the Levaditi preparations, 

 Heidenhain preparations of formalin, material, Mallory and acid- 

 fuchsin-light green preparations. In the Heidenhain and thionin- 

 eosin preparations of formol-Zenker material a similar condition 

 was demonstrated, although it was not so clear as in the above- 

 mentioned preparations. 



The protoplasm of glia cells was brought out favorably in the 

 thionin-eosin preparations, Heidenhain preparations, Mallory and 

 acid-fuchsin-light green preparations. There are two different 

 types of neuroglia cells ; in one type the protoplasm is very scanty, 

 so that the glia cell shows a small round cell body, while in another 

 type we find a large mass of protoplasm around the nucleus. The 

 neuroglia nuclei are sometimes connected with each other not by 

 means of the Golgi-net substance, but by a variously broad mass 

 of granular protoplasm. I should interpret this as the result of 

 amitosis which is observed now and then in the synapse. It must 

 be positively emphasized here, however, that all the glia cells of 

 the synapse belong to one reticulum and that there is no cell indi- 

 vidual among them in normal brains. The structure of the glia 

 nucleus hardly calls for a description except that sometimes it 

 shows evidences of amitosis, as Bartelmez (3) also stated. Cap- 

 illaries are found here and there in and about the synapse of the 

 Mauthner cell. They do not offer anything particular in their 



The figures 1 to 8 are the unretouched photomicrographs taken from different 

 preparations of both the control and the fatigued Ameiurus brains. In figures 

 2 and 5 an apochromatic Zeiss ocular no. 4 and Zeiss objective D were used; others 

 were taken with the same ocular and a Zeiss immersion iV. The length of bel- 

 lows was 60 cm. in all the photomicrographs. The figures 6 to 14 were drawn from 

 different preparations of fatigued Ameiurus brains, using the Abbe camera lucida. 

 (Zei.ss apochromatic ocular no. 4, Zeiss oil-immersion ,V. tube length 20 cm.) 



Fig. 1 Toluidin-blue preparation (alcohol material) (control fish). 



Fig. 2 Thionin-eosin preparation (formol-Zenker material) (control fish). 



Fig. 3 Toluidin-blue preparation (alcohol material) (fatigued). 



