94 DR. MARTIN BARRY ON FIBRE. 



apply themselves to one another (fig. 28), so as to present the appearance of a neck- 

 lace ; and that subsequently, as the partitions between the cell-cavities are absorbed, 

 this necklace becomes a tube. It is supposed that the ultimate threads of the tissue 

 arise within this tube. But on the subject of the particular mode of origin of these 

 ultimate threads, I am not aware that we possess any published information, except 

 that furnished by SCHWANN and VALENTIN : the former having shown that a " secon- 

 dary deposit" makes its appearance on the inner surface of the wall of the tube-f-, and 

 the latter, that this deposit soon presents longitudinal threads ; which threads have 

 sometimes the appearance of being "composed of longitudinal rows of globules^." 

 I do not find that any mention has hitherto been made of a second order of tubes, 

 arising within the first or parent tube (par. 42). The results obtained by myself 

 are by no means complete ; but may perhaps afford information that will serve as a 

 guide in future investigations. 



21. Cells applied to one another in the above necklace-like manner, I formerly 

 showed to become filled with discs . If now fig. 26 <y be referred to, such discs or 

 cells into which the discs have passed will be seen arranged in lines, corresponding 

 with the direction of the forming tube. This figure was taken from the mould of 

 cheese. Fig. 36 presents an arrangement of the same kind, noticed in voluntary 

 muscle. 



22. One of the purposes for which this linear direction occurs, seems to be the pro- 

 duction of smaller tubes within the larger one (fig. 30) ; and another purpose is ap- 

 parently a peculiar arrangement of discs within the smaller tube. Such an arrange- 

 ment is seen in figs. 45 to 48. In some of these, the discs had become rings. The 

 structure of these rings was such as to leave no doubt with me, that the same process 

 was in operation as that producing the changes, above described, in corpuscles of the 

 blood. The blood-corpuscle (fig. 17 a) passes from a mere disc into a ring (/3, y), 

 and this ring into a coil (&, t, t). Now, with the regular arrangement of rings seen at 

 a fig. 48, and with the analogy of the blood-corpuscles just mentioned, it seems highly 

 probable that every ring (fig. 48 a) becomes a coil, and that the extremities of coils 

 in the same line unite, to form a spiral. I have to add, that a spiral (y) actually 

 existed in this tube (fig. 48) in a line with the rings represented in the figure, 

 having obviously been formed out of such rings : and I know of no way in which 

 the transformation could have been effected so easily and so naturally as that now 

 described. 



23. The tube in question (fig. 48) presents, not merely one, but two spirals : and 

 these two spirals interlace with one another. This interlacement seems to explain 



t ScftwANN, " Mikroskopische Untersuchungen iiber die Uebereinstimmung in der Struktur und dem 

 Wachsthum der Thiere und Pflanzen." Tab. IV. fig. 3. 



I VALENTIN, in MULLER'S Archiv, 1840, p. 204. My observations are entirely different from those of 

 VALENTIN as to the office performed by the nucleus of the cell. 



" On the Corpuscles of the Blood," Part III., /. c., par. 161. 



