

ILLUSTRATIONS XXXIX 



FIG. PAGE 



280. Photographic Record of Effect of Ether on the Electrical Response, of 



Plant-nerve . . . . . . . . ' . \ . 472 



281. Photographic Record of Effect of CO.; on Electrical Response of 



Plant-nerve .......... 473 



282. Photographic Record of Abolition of Response by Strong Application 



of Alcohol ........... 473 



283. Photographic Record of Effect of Ammonia on Ordinary Tissue of 



Petiole of Walnut ......... 474 



284. Photographic Record of Effect of Similar Application of Ammonia 



on Plant-nerve ........... 474 



285. Photographic Record of Exhibition of Three Types of Response, 



Normal Negative, Diphasic, and Abnormal Positive, in Nerve 



of Fern under Different Conditions . . . . . . 475 



286. Photographic Record of Effect of Tetanisation in Inducing Enhance- 



ment of Normal Negative Response in Nerve of Fern . . . 476 



287. Photographic Record of Conversion of the Abnormal Di-phasic into 



Normal Negative, after Tetanisation, T, in Nerve of Fern . . 477 



288. Photographic Record showing how the Abnormal Positive Response 



is converted through Diphasic into Normal Negative by the 

 Increasing Effective Intensity of Stimulus, due to Lessening the 

 Distance between the Responding and Stimulated Points . 477 



289. Diagrammatic Representation of the Conductivity Balance . . . 482 



290. Photographic Record made during Preliminary Adjustment for 



Balance of Nerve of Fern ........ 482 



291. Complete Apparatus of Conductivity Balance ..... 484 



292. Effect of Na.,CO 3 Solution on Responsive Excitability of Frog's Nerve 485 



293. Effect of CuSO 4 on Frog's Nerve 485 



294. Photographic Record showing Enhancement of Responsivity by 



Application of CaCl. 2 ......... 486 



295. Photographic Record showing Depression of Responsive Excitability 



by Application of KC1 ......... 487 



296. Photographic Record exhibiting Comparative Effects of NaCl and 



NaBr on Responsivity ........ 487 



297. Photographic Record of Effect of Dilute (-5 per cent.) Solution of 



Na 2 CO 3 on Variation of Conductivity . . . . . . 488 



298. Photographic Record of Effect of Stronger Dose (2 per cent.) of 



Na 2 CO 3 Solution on Conductivity ...... 489 



299. RESPONSIVITY versus CONDUCTIVITY under KI . . . . 491 



300. RESPONSIVITY versus CONDUCTIVITY under Nal .... 492 



301. Effect of Alcohol on the Responsivity of Frog's Nerve . . . 492 



302. Photographic Record of Effect of Alcohol Vapour on Receptivity . 493 



303. Photographic Record of Effect of Alcohol on Conductivity . . . 494 



304. Photographic Record showing Effect of Alcohol on Responsivity . 494 



305. Diagrammatic Representation of Experimental Arrangement for 



Demonstration of RECEPTIVITY versus CONDUCTIVITY, or of 

 RECEPTIVITY verstis RESPONSIVITY 495 



306. RECEPTIVITY versus RESPONSIVITY under Alcohol . . . 495 



307. Photographic Record showing Effect of Cooling on Conductivity of 



Plant-nerve 499 



