48 



ments were then performed to decide whether the starch found in the ever- 

 green leaves ia the midst of winter is the product of carbon assimilation 

 going on at that time, or that which was formed some time before and 

 stored up there without translocation. 



The experiments were mostly made with pot-plants, the plant planted 

 in the ground being sometimes used. 



On Jan. 8, 1898 (m. t. 5 > 3.°3 C.) several leaves from each of two 

 pot-plant*, about half a meter high, were examined, the presence of a 

 little starch in lx>th of them being confirmed. Both plants were placed in 

 out-doors, the pots being buried in the ground to prevent the freezing of 

 earth within the pots ; and one of them was covered with black cylinder, 

 while the other was left uncovered for the control. 



On Jan. 23, fifteen days after, the leaves from both plants were again 

 examined, and it was found that the blackened plant lost all of the starch 

 in the leaves, while that of the plant for the control remaining constant. 



At 9 a. m., Jan. 27 the black cover was taken away from the former 

 plant, which was then exposed to light for one clear day (m. t. 2°.9) and 

 three cloudy days (m. t. l°.7-7°.0). Then the leaves were examined at 



leaf-starch on Jan 23 (m. t. 0°.7), and found pretty rich starch in both. 

 One of them was put in the dark chamber, while the other was placed in 

 outdoors for the control. 



At 9 a. m., Feb. 10 (m. t. 3°.0) the former was found to be entirely 



