92 DR. MARTIN BARRY ON FIBRE. 



plants, is that usually denominated a " fibre." And the appearance of the filament 

 in all the structures mentioned, was essentially such as that delineated in the figures 

 above referred to : an appearance which I have never before seen represented as that 

 of fibre." 



12. Most of the figures which accompany the memoir present filaments, having 

 the appearance in question. It will be seen to be precisely such as that of the filament 

 formed within the corpuscle of the blood. We know that discoid corpuscles circulate 

 in plants ; and it remains to be seen whether filaments are not formed in these. 



The foregoing facts, I think, indicate the necessity in physiological research, of not 

 resting satisfied with mere opinion, though emanating from so high an authority as 

 HUNTER; who supposed the corpuscles to be "the least important portion of the 

 blood." 



Structure of the Flat Filament (" Fibre") more particularly investigated. 



13. We have hitherto viewed the object called by me a flat filament, only in some 

 of its minutest forms. These are sufficient to show that it is a compound structure. 

 But in order to become more particularly acquainted with this structure, it is requi- 

 site to trace the filament into similar objects of larger size. For this purpose, it will 

 be sufficient to examine successively the following figures, from nervous substance, 

 from muscle, and from the crystalline lens : namely, figs. 1 17 |3, 116/3, 1 15 j8, 1 14 (3, 

 62, 53, 92, 56, 54, 84, 131. 



14. I have attempted in fig. 55. to represent what has appeared to me to be the 

 structure of the objects in the figures now referred to. Here (in fig. 55) we find two 

 spirals, running in opposite directions, and interlacing at a certain point (a), in every 

 wind. This arrangement gives to the entire object a grooved appearance and a 

 flattened form. It is in fact the structure which, for want of a better term, I have 

 called a flat filament. The edge of this filament (figs. 1 14 (3, 56 y, 62) presents what 

 at first sight seem like segments, but which in reality are the consecutive curves of a 

 spiral thread. A transverse section of such an object is rudely represented by the 

 figure 8. This is precisely the appearance presented also by the minutest filament 

 or " fibre :" and I particularly refer to the oblique direction of the line separating the 

 apparent segments in the smaller filament (fig. 9 y), in connection with the oblique 

 direction of the spaces between the curves of the spiral threads in the larger one. 



15. In further proof of identity in the structure of the larger and the smaller fila- 

 ments, it may be mentioned, that I have seen filaments of minute size to enlarge, and 

 give origin in their interior to other filaments (fig. 131). 



16. We shall hereafter find that there is a tendency in these filaments to become 

 membranous at the surface (par. 62). Hence it appears to be, that, very often when 

 the flattened form of the filament and its grooved middle part are distinctly visible, 

 no trace whatever of a crenate edge can be discerned. This may serve to show the 

 necessity for extended observation, before investigators come to a conclusion as to 



