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REMARKS ON SPINAL GANGLIA AND NERVE-FIBRES, 5879 
like pigment-granules. Between these extremes numerous 
gradations can be seen, but it must be stated that the con- 
dition of the nucleus does not seem to depend upon the size 
of the cell, as colourless vesicular-looking. nuclei may be 
found in some of the smallest cells. In cells where the 
nuclei become stained the surrounding substance appears 
more homogeneous, and also assumesa pale violet tint. In 
no instance have I ever seen more than one nucleus ina 
ganglion-cell. 
The differences in the appearance of the nuclei suggest the 
conjecture that ganglion-cells may be regenerated from this 
nucleated hyaline substance. ‘This conjecture is supported 
in some degree by the position of the smaller cells, which 
often seem as if they had been buds growing from the larger 
cells with which they are in contact. It is further supported 
by some observations of Mayer, quoted in Canstatt’s ‘ Jahres- 
bericht’ for 1874, p. 45, who states, as the result of examina- 
tion of frogs, toads, and tritons, that the so-called nuclei of 
Schwann’s sheath of peripheral nerves are originally large 
nucleated cells lying upon the inner surface of the sheath, 
and that as they participate in the regeneration process of 
the nerve they probably belong to the nerve-tissue. As I 
have been unable to obtain the original paper, I do not know 
on what ground Meyer assumes that these cells are concerned 
in the regeneration of the nerve; but if his assumption be 
correct it would apply equally well to the nucleated interior 
of the ganglion-cell capsule, which is analogous to the cells 
described by him on the interior of Schwann’s sheath. 
The existence of nucleated cells on the interior of the 
capsule of ganglion cells has long been known. Remak, 
quoted by Schwalbe in Max Schultze’s ‘ Archiv’ for 1868, 
p- 08, describes these capsules as composed of a soft cell- 
layer and of a firm membrane; Wagner and Robin, quoted 
by Fraentzel in Virchow’s ‘ Archiv’ for 1867, p. 557; Valen- 
tin, in Miller’s ‘Archiv,’ 1839, p. 189; Henle, in his 
‘General Anatomy; and Kolliker, in his ‘Gewebelehre,’ 
1867, p. 250, describe and figure such cells; but the illus- 
trations poorly represent what the appearance is as seen in 
preparations made in the manner above described. Fraentzel 
(loc. cit.) has by nitrate of silver demonstrated that this layer 
is composed of epithelial (? endothelial) plates, and in this he 
is corroborated by Schwalbe (loc. cit.) and Arndt (Max 
Schultze’s ‘Archiv,’ 1874, p. 140). The difference as to 
the number of nuclei in the corpuscles of different cells has 
been noticed by both Schwalbe and Arndt. The latter 
regards the greater number of nuclei as the result of the 
