DR. MARTIN BARRY ON FIBRE. 97 



35. The constant presence in these parts, of discs, rings, and coils, makes it diffi- 

 cult to avoid connecting them with such objects as that in fig. 22 : the outer spiral 

 in which, for instance, may represent an advanced state of coils like those in fig. 21. 

 Spirals were present between a and /3 in fig. 22 ; but they have not been delineated. 



36. In fig. 80 y, is a broad band-like axis, consisting of delicate longitudinal 

 filaments, and having filaments (|3) external to it ; these being surrounded by a 

 spiral (a). The broad band-like axis (y), I think may correspond to that of REMAK 

 above referred to ; the " white substance" of SCHWANN being here represented by the 

 filaments (3 and a. If, however, this analogy exists, my observations go farther even 

 than REMAK'S. The axis described by this observer was found by him to be suscep- 

 tible of division into filaments. So also is the one described by myself (fig. 80 <y, 

 81 /3, 85 (3). But what I add is that each filament is a compound body, that en- 

 larges (fig. 86), and, from analogy, may contain the elements of future structures, 

 formed by division and subdivision to which no limits can be assigned. 



37. The filaments (3 in fig. 85, being of far minuter size than the so-called " pri- 

 mitive fibre" of the nerves (figs. 102, 112 a, |3), I think it possible that the filaments 

 referred to in a former page, as seen by SCHWANN to proceed from one of the ordinary 

 "primitive fibres" in the mesentery of the Frog, may have had a similar mode of origin. 



38. It has been already stated that the filaments which I believe to constitute .the 

 " white substance of nervous fibre," are often seen to be, not longitudinal, but curi- 

 ously interlaced (fig. 102 y), as though each filament ran in a spiral direction. The 

 appearance has been very much like what would be produced by an elongation of the 

 spirals in fig. 60 (compare this with fig. 102 y), supposing many spirals to be pre- 

 sent instead of two. Now fig. 60, though ideal, represents, apparently, no more than 

 an advanced state of the object fig. 22. In fig. 22 the spirals a and /3 run in opposite 

 directions ; and were (3 to have attained the size of a, we should have fig. 60, with a 

 central row of nuclei for the production of other spirals, which spirals would make 

 the resemblance to fig. 102. y still more cotnplete-f-. 



39. The frequent interlacing (fig. 102 y), and apparently spiral direction, of the 

 filaments in nerves, now referred to, seems the more deserving of attention, from my 

 having found spirally directed filaments so very general in the retina, brain, and 

 spinal chord (figs. 17 to 22, 72, 77, 80 to 82, 85, 99). Farther, I have noticed spirally 

 directed filaments, on being broken, to recoil (figs. 80, 81). Such a change in the 

 " white substance," taking place within a tube, might produce varicosities ; and those 

 minute isolated masses, hitherto called granular, by which it has been usual to distin 

 guish nerve. 



40. In the course of my investigations, I met with a curious object in the lachrymal 

 gland, more resembling a nerve than any other structure, the appearance of which 



t As already mentioned, there were spirals between a and /3 in fig. 22 ; which I have not introduced. Their 

 presence gives an additional resemblance to fig. 102 y. From the above remarks, it appears that a state like 

 that in fig. 60 may be produced in two ways. See par. 27. 



MDCCCXLII. O 



