78 
Walter Gardiser. 
them” which finally gives way to an appearance of numerous and exlremely 
delicate threads which in the course of some 15 or 20 minutes afler the 
addition of the salt solution come plainly into view. They are highly re- 
fractive, frequently nodulose and usually simple threads, although in some 
instances they mav be bifurcated near their apex. At first very tense, they 
gradually beeome more and more slaek, and are finally so loose, that they 
execute lateral vibralory movements, probably caused by water currents 
due to differences of temperature. While in the tense condition they may 
rupture, and then each free end contracts, the one to the main mass and the 
other to form a minute sphere lying on the side of the ceil-wall. After 
death their refractive index appears to alter, and they beeome ropy instead 
of brilliant and sharply defined. Il is the existence of these liner threads 
which were discovered by Bower and myself. 
The attempts made to fix these plasmolytic figures did not meet with 
much success, although if a section -which has been trealed with a 10 p. c. 
salt solution, be rapidly washed in water, treated for some time with satu- 
rated watory Picric acid, and gradually transferred into weak and gradually 
stronger alcohol, it may be finally stained with aniline blue with the thicker 
threads fairly fixed. 
Naturally my great object was to endeavour to find whether in pitted 
tissue these threads bore any relalion to the pits, bul after many observations 
1 came to the conclusion that this was not the case. Very frequently when 
the plasmolytic condition is induced by the action of strong salt solution 
(10 p. c.) it can be seen that many of the thicker threads go to the pits, and 
also that in two adjoining cells many threads on different sides of the common 
pit-membranes are exactly opposite one another. Again in stained seetions 
the same fact can be demonstrated. However I find like Boweh that in as 
many if not in more instances the strings bear no relation whatever to the 
pits, and since the above phenomena attending plasmolysis take place as 
far as I am aware in all cells alike, it follows that in such cells as those of 
the epidermis or of filamentous Algae as many strings run to the free watls 
as to those which separate adjacent cells. 
In the coarser plasmolysis as caused by very strong reagenls such as 
Sulphuric acid, Chlor. Zinc. Jod., or Alcohol, I believe that the sticking of 
the threads to the pit-membranes, as observed by Hofmeister ') in Spirogyra , 
by df. Bary 2 ) in the sieve-tubes of Yitis, by Bower 3 ) in the spicular cells of 
Welwitchia and myself in the numerous instances I liave cited in this paper, 
does afford some evidence in favour of the existence of a continuity of the 
protoplasm between of adjacent cells. 
t) Hofmeister. 1. c. 
i bf. Bary. Vergl. Anat. p. 186. 
3) Bower. Quart. Journ. Micr. Sei. Jan. 1883. 
