Bram3ell & GrATKNBY — Golgi Elements of Mammalian Nerve Cell. 279 



anastomose with its neighbour. Many observers who have worked almost 

 exclusively on mammalian material, when shown the peculiar banana-shaped 

 batonettes of mollusc, annelid, insect, and other invertebrate cells, have expressed 

 doubts as to the homology of the Golgi apparatus of their material with these 

 structures in the cells of invertebrates. 



The evidence for the view that the two sets of structures are truly homologous 

 falls into the following groups : — 



1. In the neurones of invertebrates the Golgi apparatus techniques reveal an 

 apparatus formed mainly of isolated rods and batonettes. This apparatus 

 occupies the same position in both young and old neurones as does the true Golgi 

 apparatus in young and old mammalian nerve cells. 



2. The micro-chemical evidence shows that the silver nitrate techniques of 

 Golgi, Cajal, and Da Fano consistently reveal both the dendriform apparatus of 

 the mammals and the batonette or isolated elements of the lower animals. 



3. The osmium techniciues of Kopsch, Mann-Kopsch, and Sjovall likewise 

 consistently impregnate these two sets of bodies in the vertebrate and the 

 invertebrate animals. 



4. The embryological evidence shows that the so-called Golgi bodies of eggs, 

 during segmentation and histogenesis, are divided or sorted out among the 

 blastomeres and their tissue derivatives, and that finally these egg Golgi bodies 

 form the Golgi apparatus in the cells of the nervous system. Thus, cytologically 

 the Golgi bodies of the egg have been traced from the small eccentric batonettes 

 of the primitive germ cells, and embryologically their derivatives in the egg have 

 been traced into the nerve cells of the new organism. The chain is therefore 

 complete. 



5. In many vertebrate animals (e.g. the frog) the Golgi apparatus of the 

 nerve cell is formed of elements intermediate in shape and appearance between 

 the banana-shaped genital element of invertebrates and the tree-like or net-like 

 elements of the mammalian neurone. 



It must then be admitted, especially in view of the embryological evidence 

 (Hirschler and Gatenby, 3 and 6), that there is a complete continuity between 

 the genital Golgi element and the nerve Golgi element. Some observers have 

 expressed doubts as to the reliability of the various silver nitrate techniques; 

 our e^ddence, however, does not depend solely on similarity of micro-chemical 

 reaction. On the other hand, we recognise fully that the techniques of osmic acid 

 and silver nitrate often reveal wide differences in micro-chemical reactions 

 between the batonettes of invertebrate genital cells and the Golgi apparatus of 

 mammalian cells : this is not a serious matter, however, because equally wide 

 micro-chemical differences exist not onlj- between the Golgi elements of different 

 animals, but also betAveen the Golgi elements of different tissues of the same 

 animal. 



We believe that the evidence adduced in this paper is sufficient to prove that 

 the batonettes or nebenkern rods of such an animal as Helix, the snail, are 

 homologous with the remarkable Gfolgi inner network of the mammalian 

 neurone. 



Summary. 



1. The Golgi apparatus in the smallest neurones of Helix was in the 

 perinuclear extra-centric position, suri'ounding an archoplasmic sphere. In 

 larger neurones it liecomes dispersed around the nucleus and the individual 

 elements become much more numerous. 



2. Basophil granules, jirobably representing the tigroid body, and also 

 lecithin (?) granules, are described in the neurones. 



SCIKNT. PROC. K.D.S., VOL. XVII, NO. 84. 3 F 



