698 DR ALEXANDER BRUCE AND DR JAMES W. DAWSON ON 
have led, amongst other things, to a new interpretation of the nature and mode of develop- 
ment of the new growths which arise in relation to nerves. They have given a new 
significance and a new conception to the term ‘“‘ neuroma,” as they have also reaffirmed 
the existence of the “true” neuroma as a definite group of tumours. 
The term neuroma conveys to many minds no definite conception. Optmr, in 1803, 
suggested the name to designate “ deep-seated tumours which are characterised by pain- 
ful swelling of the nerves involved.” The term came into use to indicate any tumour 
in relation to a nerve, thus indicating its most important clinical feature, whatever its 
histological structure might be. Early writers ascribed their origin to an overgrowth 
of the connective-tissue sheaths of the nerve, and apparently took it for granted that a 
tumour composed of nerve tissue could not exist. VrrcHow, in 1863, placed the path- 
ology of neuroma on a histological instead of a clinical basis, when he distinguished 
between true neuroma (neuroma verum) and false neuroma (pseudo-neuroma). True 
neuromata arise in the nerve tissue, and nerve tissue enters into them as an essential 
constituent, Halse neuromata arise in the interstitial connective tissue of the nerves. 
True neuromata were further divided into “‘ neuroma ganglio-cellulare,” containing newly 
formed nerve cells; neuroma fibrillare amyelinicum, containing chiefly non-medullated 
nerves; and neuroma fibrillare myelinicum, consisting chiefly of medullated fibres. 
VircHow stated that the nervous nature of many neuromata had been overlooked 
because the non-myelinated fibres had been mistaken for connective-tissue fibres, and 
because many of the fibres, both medullated and non-medullated, had disappeared 
through pressure and had been converted into connective-tissue-like elements. This 
classification was regarded as unsatisfactory, especially by those who considered nerve 
fibres as the processes of ganglion cells, and who thought, therefore, that there could 
be no fasciculated neuroma without ganglion cells, because nerve fibres are elements 
incapable of proliferating independently of the cell with which they have a direct 
connection.* 
The present paper is founded on material derived from a patient who had suffered 
from spastic paraplegia, and in whose spinal cord, medulla oblongata, and pons, multiple 
fasciculated neuromata were found. In these nodules no ganglion cells could be traced, 
and nerve fibres, of the structure of peripheral nerves, were present in different stages 
of development. Inasmuch as the elements of a tumour differ from the tissues in which 
they take their origin, and the diversity frequently consists in a return to the embryonal 
phases of the elements themselves, it seemed necessary, in considering the case, to study 
the literature bearing upon the development of peripheral nerves in order to arrive at a 
true solution as to the genetic relation of the elements. Further, as in regeneration of 
nerves these embryonal phases of development are often reproduced, the literature on 
the regeneration of nerves after section was next investigated. And, finally, as patho- 
* For a further consideration of this subject, see under I. (3), p. 780. 
