MULTIPLE NEUROMATA OF THE CENTRAL NERVOUS SYSTEM. 699 
— logical histology has often shed light on normal tissue development, the literature bear- 
ing on tumours related to nerves has passed under review. Aided thus by collateral 
evidence adduced from the three sources of embryogenesis, regeneration, and tumour 
formation, an endeavour has been made in the following paper to give an interpretation 
of the histological picture which a study of numerous nodules revealed. The considera- 
tion of our work will thus be carried out under the following headings :— 
I. The Genesis of Peripheral Nerves : 
(1) Embryogenesis: with a note on the genesis of fibres in the central nervous 
system. 
(2) Histogenesis in Regeneration after Section: with a note on regeneration of 
fibres in the central nervous system. 
(3) Histogenesis in Tumour Formation :—(q@) ganglio-neuroma ; (>) neuroma ; 
(c) neuro-fibroma: with a note on genesis of fibres in tumours of the 
central nervous system :—(a) glioma and neuro-glioma; (b) neuroma. 
II. Histological Study of Multiple Neuromata of the Central Nervous System. 
IIf. Interpretation of Observations and Conclusions. 
I.—THE GENESIS OF PERIPHERAL NERVES. 
a 
GENERAL REMARKS ON THE STRUCTURE OF THE PERIPHERAL NERVOUS SyYSTEM.* 
Almost the whole of neuro-pathology rests on the neurone doctrine, which sees in the 
-axis-cylinder a prolongation of a central cell. The problem of the relation of the nerve 
fibre to the nerve cell involves a consideration of facts relating to the continuity or 
independence of the central cell and its peripheral ramifications. The old reticular 
theory of GuERLacH, who saw in the nervous system an uninterrupted protoplasmic 
network, was destroyed by the findings of Goner in 1875 and Casau in 1891. These 
observers, by specific staining methods, showed the existence of free terminations of 
‘the processes of the ganglion cells and of the axis-cylinder ramifications—a mere 
7 relation of contiguity of elements being thus indicated. In 1891 WaLpEYER put 
forward the view that the nervous system is constituted of an infinity of anatomical 
units which, embryologically, are independent of each other. He proposed the term 
“neurone” to designate the cellular unit formed each of a ganglion cell, its nerve fibre 
_ process, and protoplasmic processes with their terminal ramifications. The simplicity 
of this view is greatly in its favour, for the ensemble constitutes a cytological unit 
developed from a single central neuroblast. 
The conception of the cell-chain theory is opposed to the neurone doctrine. The 
nerve fibre, according to this view, represents a chain of special cells (segmental neuro- 
blasts) secondarily brought into relation to the central cell. In each element there 
has differentiated from its individual protoplasm a fatty substance (myelin) and a 
* Based on “ Nerfs,” by G. Durante, in Manuel d’ Histologie Pathologique, Cornil et Ranvier (Paris), 1907. . 
