( 392 ) 



Physiology. — 'A nc/r hur (■{inci'i'iihiij ijic lU'ldlloii hii.irci'ii slim ill iis 

 (111(1 ('tf'i'ct.^' J>y Dr. J. K. A. Wehthkim Sai.omonson, c-uiiiimi- 

 iiicated I)v ])r. C. Winki,kh. (Conimiinicatioji IV). 



Ill three papers, heai'iii.u- llie (ille "a new law (•oiicei-iiiiiu- the relation 

 l)etweeii stiiiniliis and eileet 1, II and III. I have ti-ie<l to prcne that 

 by increasing' a stininlns, the eHeet too will inerease in a delinite 

 manner. 



The relation Avas expre^-sed Ity the tonnula 



E=A{l-e~^i(R-c)) (1) 



In deduein.U' this fonnida I assumed that the traiislornialion of 

 ehemieal substance caused one and only one ',\ (dl-detine<l eiteet. 



In most cases however from snch a transformation several conse- 

 quences will result, constitutinu' to,neth(>r the total effect : e.U'. aniecha- 

 nical, a thermal, a chemical, an electrical effect may be caused simul- 

 laneously by some clian«iin<i- of the j)rotoplasma. 



The (jiiestion arises, whether our mathematical exj)ression may b(> 

 applied as \\ell lo the diffei-ent |tarls of an effect as to the total 

 effect. In ord(>r to obtain an aiiswci- to this (pieslion, we have to con- 

 sider a.U'ain the differential (Mpialioii: 



— (IK — BK.in (2) 



•expressin,u-. thai l»y an iiiiinilesimal increment of stimidus an iiiliiii- 

 tesiinal proportional part of the translbi-mable substance was trans- 

 formed, and at the same time statini»' the <(iiaiilily of this ti-ansfoi-ma- 

 tion. I'he (piantity — (IE re|)reseiits the ineicment of the effect. In 

 the case of the effect beinu' composed of sexeral different ])arls, 



the same etpiality w ill pre\ail for any of them, e.i:. the pari, and 



)i 



80 Ave shall oblain for a pdrthd effect the (Mpialion 



1 

 clE — BE(lR (3) 



in which ii ^ \ . 



From this formula we ,üet the expression 



E=ia\l— e-»n(ii-') \ (4) 



wherein a represents another constant than J, hud wherein /i is a 

 number laro-cr than J. 



This formnla for a partial effect is identical to the formula for a 



