484 



Dr. A. D. Waller. 



Influence of Lowered Temperature upon Direct Eesponse 

 of Frog's Skin. 



Time. 



Temp. 



Normal 

 current. 



Tel an. 1000 + . 



Tctan. 1000 --. 



mins. 



18° 



-0/03 



+ 0'X)U2 



+ 0-0083 





10° 





+ -0125 



+ 0-0085 





0° 



-o-oi 



+ -0075 



+ -0085 



30 „ 



-2° 





+ '0042 



+ -0060 





-4° 





+ 0-0028 



+ -0035 





-6° 





[spontaneous + '0035] 



60 „ 



-6° 



-000 



+ -0015 



-0*0010* 



-6° 





-0-0005 



+ -0005 



* To single break shocks 10,000 + and 10,000 — . There was no response 

 to 1000 + and — . 



Note. — At —6° there was a sudden positive deflection, of electromotive source 

 and not due to any sudden alteration of resistance, presumably indicative of 

 excitation at the instant of congelation. 



The signs + and — as regards tetanisation by alternating induction currents, 

 refer to the direction of the break shock. Thus 1000 + signifies 1000 units of 

 Berne scale, break shock outgoing (and make shock ingoing) through the skin. 



With a dead skin, the deflections due to polarisation are in the direction of the 

 break current, presumably by reason of superior polarisation by makes over breaks. 

 (Cf. ' Proc. Physiol. Soc.,' November 12, 1898.) 



With skin in this state, strong single shocks give rise to the ordinary polarisation 

 counter currents. 



