1905.] Distribution of Chlorides in Nerve Cells and Fibres. 183 



velocity of migration of the ions, and Traube, in his comments* on the same 

 paper, remarks that the formation of the vesicular and reticular structures in 

 cell protoplasm are due to the same process that evolves the rings and striae 

 described by Liesegang. 



In order to study the relation of these striae to those found by Frommann 

 in medullated nerve fibres, we prepared capillary tubes with filtered egg 

 albumen, cut them into short pieces 10 to 15 mm. in length, and placed them 

 in the N/10 nitrate of silver solution containing I'd per cent, of free nitric 

 acicl. They were observed under the microscope with powers magnifying 

 from 90 to 590 diameters, and the progress of the reaction, exposed as 

 the tubes were to a bright sunlight, could be followed from point to point 

 readily because of the reduction of the silver chloride. This reaction 

 advanced from both ends of each section but it usually ceased before the 

 middle of the tube was reached. 



In every case the striae appeared pronounced. The appearances which 

 they gave are represented in figs. 20 and 21, a being the part of the column 

 nearest the entrance of the tubes. In both it is seen that the striae cease at 

 a point beyond which only a general and diffuse precipitation of silver chloride 

 is found. This is not always the case, for one finds in some tubes also where 

 the striae cease, so likewise does the precipitation. With a higher magnifica- 

 tion it is shown that the interstriate zones contain a fine precipitate whose 

 occurrence may be overlooked. It is to be noticed also that the borders 

 of the striae are not linearly or sharply defined, for the granules are often 

 scattered and sparse at the edge of the stria, but in its centre they are densely 

 aggregated. It is found also that there usually is a gradual broadening of 

 both the striae and the interstriate zones as one follows the column inwards, 

 and the striae become at the same time less and less distinct until, as 

 represented in fig. 21, they are lost in the ordinary precipitate. Sometimes 

 an interval of unstriated material, showing an irregularly disposed precipitate, 

 interrupts the striated column at one end, and sometimes also the interruption 

 may be very short, and of such an appearance as to suggest a complete fusion 

 of several striae. Now and then one may find that the interruption is 

 intensely coloured, this apparently depending on a greater concentration of 

 sodium chloride in the albumen at the point than elsewhere in the tube. The 

 striae on either side of the interrupting area may be very dissimilar in breadth 

 and not belong to the same series. 



In order to determine whether concentration of the chlorides in the 

 albumen would influence in any way the character of the striation, we added 

 to portions of the albumen enough sodium chloride to make the concentration 



* Ibid., p. 145. 



o 2 



