344 Prof. J. S. Macdonald. [Apr. 17, 
from the state of simple aqueous solution. The osmotic pressure in B has 
fallen. Considering the effect of this upon C only, we perceive that a 
diffusion will now tend to take place from C to B. Thus, C will now 
become negative, and, consequently, the site of liberation of electrolytes, 
and of increased osmotic pressure. Similarly, in its turn, D will become and 
remain positive, E negative. Further onwards, every alternate segment will 
similarly be rendered negative, and the site of an increase in osmotic 
pressure, until the process has dwindled away, as finally it necessarily must. 
An BS Ca Dh EE 
Ae Bie Cr DEE 
UT) NUE) TT 
The process is therefore, within limits, transmissible, and, although 
evidently unsuited as the basis of function of a tissue, the prime necessity 
of which is conduction, is, nevertheless, possibly suited to the requirements 
of a tissue in which the maintenance of a state of increased osmotic pressure 
is required in alternate segments of the tissue. Conceivably, such a process 
might be suited to fulfil some of the requirements of striated muscle. 
Glancing at the accompanying diagram, we see the result of such a process 
in an arrangement of alternating segments of high and low osmotic pressure 
respectively. Compare such a diagram with Macallum’s representation of 
the potassium salts in muscle, and there is a similarity which is at once 
worthy of examination. 
I have already stated above that, in my opinion, Macaélum’s representation 
must be interpreted as evidence of the existence in muscle (probably in the 
contracted state) of such a disposition of alternating levels of pressure. Nor 
need we depend only upon this observation, since Schafer has, some con- 
siderable time ago, recorded observations depicting a flow of water from 
disc to disc of the muscle sarcostyle, such as this condition of alternating 
segments of high and low osmotic pressure would determine. There is 
therefore ample reason to inquire further into the possibilities of this 
process. 
Let us for example inquire how such a strip of material would react to a 
mechanical extension. Mechanical stimulation it is safe to assume would lead 
to a general tendency towards desolution along the strip in each of the 
segments into which we have divided it This tendency, from reasons 
previously given, would affect most the segments in which desolution had 
already taken place. In other words, an increased load would lead to an 
exaggeration of the preceding condition of contraction. 
