/ 113 



the opening is bright yellow and fleshy, but after the opening it dries 

 more or less and becomes somewhat brown. The reclosed flower opens 

 again within the following night and closes no more till it falls about the 

 noon of the third day. So the duration of the flower can be said to 

 be 2.^ days. This duration is not much altered even when the rain 

 and wind act mechanically upon it. 



One other point to be remarked here is the rise of temperature at 

 the time of flowering. Caspary 13 observed that the rise cf temperature in 

 the flower of Victoria regia at the time of flowering was about 15°C, above 

 the surrounding atmosphere. I found in the time of the flowering of 

 Nelumbo nucifera, that the temperature rose 10° above that of the 

 atmosphere. My method of observation is rather rough one. The 

 thermometer was thrusted into the flower which was just opening, after 

 10-15 minutes it was taken out and examined. At one time the read- 

 ing of the thermometer was 35°C, the atmospheric temperature being 

 25°. In two other cases the thermometer was thrusted a little after the 

 opening, and found that the rise of temperature was S J in both cases. 



3. On assimilation and transpiration.^ 



• 

 Somewhat circular shaped leaf of Nelumbo has the diameter, 40-80 

 cm., so that a single leaf has the area 12-50 dm 2 . The organic 

 matters produced by the assimilation in a leaf having such a vast area 

 would be remarkable. To estimate the accumulation of assimilated products 

 in the leaf; within certain intervals of times, I attempted to find it out 

 roughly by comparing its dry weight in the morning and afternoon, as 

 Sachs 3) did in his well known work on assimilatory action of leaves. 



In the clear morning. 6 ,\ a. m. of 23, August, I cut out the square 

 of 1dm 2 . from each ofj ten different leaves. Ten such pieces of 

 leaves, which weighed when fresh about 18 gi\, were directly put into the 

 hot air-bath, and dried in 100° till no more decrease of weight took 

 place. After taking them out from the air-bath, cooled in the sulphuric 



1) Caspary, Uber Warrneentwicklung in der Bliithe der Victoria regia. Monatsbericht 

 der konig. preus. Akad. d. Wiss. zu Berlin, Dec. 1855. 



2) The observations on transpiration was mainly made by my friend Mr. Kusano, to 

 whom I wish to express my hearty thanks. 



3) Sachs, Ein Beitrag zur Kenntniss der Ernahrungsthatigkeit der Blatter. Arb. d. 

 Bot. Inst, zu Wurzburg, Bd. Ill, Heft I, 1884. 



