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MULTIPLE NEUROMATA OF THE CENTRAL NERVOUS SYSTEM. 749 
connective tissue between them. ‘The nodule was defined from the surrounding healthy 
white matter by a deeply-staining layer of connective tissue, and through its centre ran 
a thin-walled blood-vessel. 
On the left side the nodule was not defined from the surrounding tissue, and from 
its outer and anterior aspects radiated fine pink lines which, in their radiation, give off 
fine fibrils which enclose the adjoining normal fibres of the white matter with a pink 
zone—giving the impression that a very fine fibrillar connective tissue had in some way 
secondarily involved the fibres. Under high power the nodule had the same structure 
as that on the right side, and the pink lines were found to enclose very finely-calibred nerve 
fibres in which the yellow-staining myelin and central axis-cylinder could be recognised 
—the deeply-stainmg pink contours being gained by the increase of the connective 
tissue around these scattering fibres of the nodule. The vessel, found in relation to 
this nodule, was situated eccentrically, but in adjoining sections it assumed a more 
central position. 
The very defined nature of the nodule (fig. 19) enclosed by a dense layer of connec- 
tive tissue, staining intensely pink with the fuchsin, gave the impression, under low 
power, that we were dealing with a nodule that had arisen in relation to the vessel-wall 
itself, possibly of the nature of a leio-myoma or of an endarteritic process. Higher 
magnification, however, revealed the nervous nature of the fibres, and subsequent sections 
stained with Cajal’s and Weigert’s methods showed the presence of numerous similar 
nodules and confirmed their nervous nature. 
The first silver preparations examined were a serial set in which the nodule 
represented in figs. 8 and 29 was found. A description of the very varied nature of 
the nodules will be attempted later, but meanwhile we may note the beautiful whorl- 
arrangement of the fibres composing this one. 
The first Weigert preparations (figs. 26 and 27) also gave beautiful nodules with 
a marked intertwining of the fibres. High-power examination showed that the 
internodal segments were short and irregular, and that the myelin sheath, though 
staining specifically, was thinner and not so intensively stained as the surrounding 
fibres of the white matter. 
(a) Disposition of the Fibres forming the Nodules. 
To recognise this it will be necessary to compare Van Gieson, silver, and Weigert 
preparations. The smallest and simplest neuroma formations are mere strands of 
fibres running parallel to each other: not strictly straight, but usually sinuous. 
Such simple strands, composed of from six to twelve fibres, were most frequently met 
with in the pia lateral to the emerging anterior roots (fig. 39). An increasing 
complexity in the structure was initiated by an interlacing of the fibres as if these 
sinuous parallel fibres began to wind in and out amongst each other: such fibres were 
met with most frequently in the walls of blood-vessels cut longitudinally (figs. 32 and 
