Researches on Growth and Movement in Plants. 



365 



by this new method for the last six years ; the experiments have been 

 repeated year after year on a variety of plants and with consistent results. 



A. The High Magnification Ckescogkaph. 



1. Method of high magnification. 



2. Automatic record of the rate of growth. 



3. Experimental adjustments. 



4. Determination of latent period and time-relations of response 



to stimulus. 



B. Effect of Indirect Stimulation. 



5. Mechanical and electrical response. 



6. Effect on growth. 



C. Tropic and Nastic Movements. 



7. General considerations. 



8. Tropic curvature with longitudinal transmission of stimulus. 



9. Geotropism. 



10. Tropic curvature with transverse transmission of stimulus. 



11. Mechanotropism ; twining of tendrils. 



12. Galvanotropism and electrotropism. 



13. Thermonasty. 



14. Positive phototropism. 



15. Dia-phototropism and negative phototropism. 



16. Eadio-thermotropism. 



17. Photonasty. 



D. Eelation between Eesponse to Stdidlation of Non-growing 

 AND of Growing Organs. 



18. Similarity of response of growing and non-growing organs. 



A. The High Magnification Crescograph. 



I secured high magnification by means of a compound system of two or 

 more levers. The plant is attached to the short arm of a lever, the long 

 arm of which is attached to the short arm of the second lever. If the 

 magnification by the first lever be m, and that by the second n, then the 

 total magnification would be ran. 



2 G 2 



