Cited by I.L. Tuckett, 'On the Structure and Degeneration of Non-Medullated Nerve Fibres', Journal of Physiology 19 (4) (1896), pp. 267-311.
Description:

Explanation of Plate III (figs. 14-16):

'Figures 2, 3a, 3b, 6, 7, 8, 9, 10, 11, 12, 13a, 13b, 14, 17, 18a, 18b, 19, 20, 21a, 21b, 21c, 21d, 21e are drawn with camera lucida and ocular 4, objective V Leitz, magnification 850 diams.

Figures 4a, 4b, 5, 13c, 13d, 15a, 15b, 16a, 16b, 16c, 16d, 16e are drawn with camera lucida and ocular 4, objective 7 Leitz, magnification 590 diams. 

All the figures with the exception of 18 a and 18 b are reduced by 1/3 from the original magnification. The shades of colour in the specimens are represented in the figures as nearly as may be, but it is difficult to get an exact reproduction of the various shades of blue produced by Delafield's heematoxylin and chinolin, Grübler's haematoxylin, methylene blue.' (309)

'Fig. 14. Fibres of Remak from the carotid canal of a rabbit. Teased in aqueous humour. Osmic acid 1 per cent. Grubler's haematoxylin eosin (lightly stained). These fibres if anything are rather shrunken: and, not being flattened by the above treatment as in Fig. 6, they do not show a fibril appearance: (a) nucleus, (b) core of fibre enclosed in sheath.

Fig. 15 a. Teased preparation of splenic nerve of ox. Ammonium bichromate 2 per cent. four months. Haamatoxylin and chinolin two days: (a) nucleus: (b) isolated varicose core of a fibre, (c) sheath of a fibre.

Fig. 15 b. Isolated varicose cores of fibres from the same preparation.

Fig. 16 a. Two fibres of Remak from the left carotid canal of rabbit, No. IV. After 27 days of degeneration. Corrosive sublimate. Haematoxylin and chinolin: (a) nucleus, (b) sheath.

Fig. 16b. Fibres of Remak from the left carotid canal of rabbit, No. XXI. After 62 days of degeneration. Treatment as above: (a) nucleus, (b) shrunken fibre of Remak.

Fig. 16 c. Fibres of Remak from the left carotid canal of rabbit, No. XXVII. After 89 days of degeneration. The sheath, which alone remains, is very much broken into fibrillae. Treatment and lettering as above.

Fig. 16 d. Fibres of Remak from the left carotid canal of rabbit, No. XXII. After 125 days of degeneration. Treatment and lettering as above.

Fig. 16 e. Fibres of Remak from the left carotid canal of rabbit, No. XXVI. After 162 days of degeneration. Treatment and lettering as above.' (310-311)

 

Figs. 14-15 in text:

'The question now arises: With what part of the fibre are they connected? With the inner core of the fibre of Remak, or with the outer part which stains well, and readily splits into fibrils? There can be no doubt that they are in connection with the outer part of the fibre, and that the two together form a sheath for the inner core which is the process of a nerve-cell and carries the nervous impulse. 

The reasons for this view, which are as follows, prove at the same time that the part of a fibre of Remak which stains with methylene blue is the core.

(1) If a nucleus be detached, more often than not ragged fibrils from the outer part of the fibre are seen clinging to it. 

(2) When a piece of nerve is stained with a solution of methylene blue in aqueous humour, the fibres which appear are uniformnly cylindrical, with a diameter of about 1µ (Fig. 13 b), and they show no swellings indicating nuclei such as do the fibres in Fig. 14. Therefore the nuclei must be outside this fibre staining with methylene blue, which must, consequently, be the core of a fibre of Remak. 

(3) When the fibres of Remak are brought out by Golgi's method (Fig. 5), or by a solution of methylene blue in .6 per cent. (Fig. 13 a), salt solution, varicosities appear on them as we have seen. But these varicosities are of such a size and shape that they could not contain the nuclei. Therefore the nuclei must be outside the core of the fibre in which is deposited the silver chromate precipitate. 

(4) A transverse section of fibres of Remak shows that the nuclei are in connection with the outer paxt of the fibres rather than with the inner core, for the outer part of the fibre is sometimes seen to proceed from the edges of the nucleus over the core, which often makes a groove in the nucleus (Fig. 9), as it passes by it.

(5) If, as Ranvier directed, a piece of splenic nerve be left in ammonium bichromate for several months, then the fibres of Remak are found to be very varicose: if now they are stained for two days with hematoxylin, the nuclei and the outer part of the fibres are stained to excess;.that is, have become almost black, while the core has at length after two days taken up a certain amount of stain and come out fairly distinctly (Fig. 15). It is now found that the core is varicose and quite independent of the nuclei, while the outer part of the fibres, much broken into fibrillae, adheres to the nuclei.' (281-282)

 

Fig. 14 in text:

'fibres can sometimes be seen which have not split up, and in this case they are found to be cylindrical and to have a diameter of 1.5µ to 2µ, whereas, when they split into fibrils, the fibrils spread out and give the fibre a flattish appearance and an apparent diameter of 3µ or even 4µ [note: 'Cf. Key and Retzius' description of fibres of Remak (p. 270 supra).']. This appearance of intact cylindrical fibres of Remak is shown in Fig. 14 and should be contrasted with the crushed fibres shown in Fig. 6. 

This Fig. 14 brings me at once to the question of the nuclei, for here there can be no doubt that the nuclei are inside or embedded in the outer part of the fibre. This is seen here so clearly because the nuclei have been very lightly stained. If, as is usually the case, they are stained deeply, as in Fig. 6, they come out so much more prominently than the rest of the fibre that they stand out and appear to lie on the surface of the fibre.' (280-281)

 

Fig. 16 in text:

'With Corrosive Sublimate. In teased preparations the nuclei may be seen to be similar to normal nuclei and the general appearance of the preparation is very similar to normal preparations. But on the whole, I have come to the conclusion that the fibres of Remak seem to consist more than ever of fibrils, and to have a smaller diameter as if something was wanting. Still I do not believe that an observer who had not just been looking at normal non-medullated nerves would be able to distinguish a degenerated from a normal preparation (Fig. 16, a, b, c, d, e).

Osmic Acid. In these preparations it is very necessary to make certain that the fibres under examination are really isolated fibres. For the treatment to which the fibres have been subjected, if it does not isolate the fibres, is very apt to make two or three run together and simulate a very broad fibre of Remak, in which condition various and very curious appearances are sometimes seen (Figs. 19 and 20). In normal fibres, properly isolated, the core is seen to be very finely granular, so as to give an appearance like ground glass. In degenerated nerves after two days the core is seen to be more coarsely granular; which appearance is characteristic of degeneration as long as any core remains. The disappearance of the core varies in different animals: sometimes I have found very little left on the fifth day; sometimes some still remaining on the twelfth day. When the core has disappeared the degenerated preparation can at once be detected by the shrunken state of the fibres; and this is the most obvious sign of degeneration (Figs. 21, a, b, c, d, e). The sheath of the fibres and the nuclei do not seem to be affected by degeneration.' (294)