ILLUSTRATIONS 



FIG. PAGE 



1. Series of Contractile Responses in Muscle ...... I 



2. Response of Indiarubber ......... 2 



3. Response of Selenium to the Stimulus of Light ..... 3 



4. Negative Response of Galena to Hertzian Radiation .... 3 



5. Positive Response of Ag' to Electric Radiation . .... 4 



6. Electric Response in Metals . . . . . ... 5 



7. Uniform Electric Response in Tin ....... 6 



8. Fatigue in the Electric Response of Metals ...... 7 



9. Stimulating Action of Na 2 CO a on Electric Response of Platinum . 8 

 10. Abolition of Response in Metal by Oxalic Acid . . . . . 9 

 n. Response by Method of Relative Depression ..... 9 



12. Arrangement for observing Simultaneous Mechanical and Electrical 



Responses 17 



13. Simultaneous Mechanical and Electrical Responses in Biophytum . 19 



14. Photographic Record of Electrical Response by Galvanometric 



Negativity of Pulvinus of Mimosa, when leaf is physically 



restrained from falling . . . . . . . 20 



15. Method of Transmitted Stimulation . ...... 24 



16. Excitation by Sudden Tension ........ 25 



17. Excitatory Response to Tension and Compression .... 26 



1 8. The Mechanical Tapper . . 26 



19. The Torsional Vibrator 27 



20. The Vibratory Stimulator .30 



21. Complete Apparatus for Method of Block and Vibratory Stimulation . 31 



22. Influence of Suddenness on the Efficiency of Stimulus . . . . 32 



23. Spring Attachment for obtaining Vibration of Uniform Rapidity . 33 



24. Additive Effect 34 



25. Response Recorder 34 



26. Photographic Record of Uniform Responses (Radish) . . . . 36 



27. Stimulation by Thermal Shocks 38 



28. Photographic Record of Uniform Response in Petiole of Fern to 



transmitted excitation ......... 39 



29. Taps of increasing strength 1:2:3:4 producing increased response 



in leafstalk of turnip 39 



