560 LWE MOV^MfiNTS IN PLANTS 



of the movement of the plant shows a striking parallelism ; 

 the different plant-organs became erected from thermal-noon 

 to thermal-dawn, and underwent a fall from thermal-dawn 

 to thermal-noon. The descent of the curve is, as in the 



Fig. 20^.— Diunial curve of the procumbent stem of Tropcolam majus, and 

 the leaf of Dahlia for two successive days. In the thermographic record the up- 

 curve represents fall, and down-curve rise of temperature. 



case of thermal curve, relatively more abrapt. The records 

 on two successive days are very similar, the slight differ- 



