734 DR ALEXANDER BRUCE AND DR JAMES W. DAWSON ON 
fibres: the non-medullated fibres formed the great mass of the tumour, and the 
medullated fibres showed a weakly developed myelin sheath. Knauss thought the 
presence of the medullated fibres a confirmation of VircHow’s statement that 
myelinated neuromata have a first non-myelinated stage. None of the non-medullated 
fibres could be traced to the ganglion cells, nor was there any visible connection with 
any filaments of cerebro-spinal nerves. He regarded the tumours as having arisen 
from the minute ganglia intercalated on the fine terminal fibres of the sympathetic 
system in relation to blood and lymph vessels. Knauss thought that a true neuroma 
without ganglion cells could not occur, though in this case he could trace no connection 
between the nerve fibres and the processes of the ganglion cells. 
BENEKE (1901) records two cases of ganglio-neuroma: the one related to the 
cervical sympathetic, the other to the semilunar ganglion. Microscopically the 
tumours consisted of a felt-work of nerve bundles with groups of ganglion cells 
between them. The cells had in general the character of sympathetic ganglion cells : 
some were very small with no processes, while others were large with very numerous 
processes. The neurite of many cells could be traced in direct continuity with the 
nerve fibres, and indeed a direct continuation of the cells of the capsule with 
the cells of the sheath of Schwann was frequently noted. The non-medullated 
character of the nerves was in proportion to the non-medullated. constitution of a 
normal sympathetic ganglion, and the development of the nuclei was par passu with 
the development of the nerve bundles. The question whether mature ganglion cells 
are capable of division cannot be answered affirmatively from Beneke’s work, but he 
derives all the nerve fibres from the ganglion cells of the tumour. The fact that the 
nerve fibres preponderate is explained by the division of one axis-cylinder into its 
primitive fibrils. 
OBERNDORFER (1907) describes a ganglio-neuroma in the medullary substance of the 
adrenal which contained groups of cells separated by septa of non-medullated nerve 
fibres and connective tissue. The cells were of all sizes, from that of a lymphocyte with 
all possible transitions to cells four or five times the size of ordinary sympathetic 
ganglion cells. Some of the cells, therefore, have the same morphological structure as 
the primitive cells from which both the sympathetic nervous system and the medulla of 
the adrenal develop. Ganglion cells were found in the meshes formed by interlacing 
naked axis-cylinders, and only in the marginal part of the tumour were there any axis- 
cylinders with sheaths of Schwann. The presence of medullated fibres could not be 
proved. The naked axis-cylinders with ganglion cells reminded OBERNDORFER of an 
embryonic nerve tissue, z.e. neuroblasts with their offshoots. He concluded that the 
smaller cells were the earlier forms of the ganglion cells and thought it possible that in 
early embryonal life these had separated themselves, retaining their embryonic 
condition, till later some influence awakened their slumbering developmental possi- 
bilities, and they developed their morphological form of sympathetic ganglion cells, 
OBERNDORFER believes that every true neuroma must be a ganglio-neuroma, 
