134 DROSERA ROTUNDIFOLIA. [Chap. VII. 



whereas in the water the inflection of the three leaves which were 

 the most affected, as well as of all the others, began to decrease 

 during this same interval. It is also remarkable that the blades 

 of three of the leaves in the solution were slightly inflected, and 

 this is a most rare event with leaves in water, though it occurred 

 to a slight extent in one (No. 1), which seemed to have been in 

 some manner accidentally excited. All this shows that the solu- 

 tion produced some effect, though less and at a much slower rate 

 than in the previous cases. The small effect produced may, how- 

 ever, be accounted for in large part by the majority of the leaves 

 having been in a poor condition. 



Of the leaves in the solution, No. 1 bore 200 glands and re- 

 ceived 4,^00 of a grain of the salt. Subtracting the seventeen ten- 

 tacles which were not inflected, each gland could have absorbed 

 only the ^ T glooo of a grain (.00000738 nig.). This amount caused 

 the tentacle bearing each gland to be greatly inflected. The blade 

 was also inflected. 



Justly, eight leaves were immersed, each in thirty minims of a 

 solution of one part of the phosphate 21,875,000 of water (1 gr. to 

 5000 oz.). Each leaf thus received raljsis of a grain of the salt, or 

 .00081 mg. I took especial pains in selecting the finest leaves from 

 the hothouse for immersion, both in the solution and the water, 

 and almost all proved extremely sensitive. Beginning as before 

 with those in the solution: 



( 1 ) After 2 hrs. 30 m. all the tentacles but twenty-two inflected 

 but some only sub-inflected; the blade much inflected; after 6 hrs. 

 30 m. all but thirteen inflected, with the blade immensely inflected; 

 and remained so for 48 hrs. 



(2) No change for the first 12 hrs., but after 24 hrs. all the 

 tentacles inflected, excepting those of the outermost row, of which 

 only eleven were inflected. The inflection continued to increase, 

 and after 48 hrs. all the tentacles except three were infleote<l, and 

 most of them rather closely, four or five being only sub-inflected. 



(3) No change for the first 12 hrs.; but after 24 hrs. all the 

 tentacles excepting those of the outermost row were sub-inflected, 

 with the blade inflected. After 30 hrs. blade strongly inflected, 

 with all the tentacles, except three, inflected or sub-inflected. 

 After 48 hrs. in the same state. 



(4) to (8) These leaves, after 2 hrs. 30 m., had respectively 32, 

 17, 7, 4, and 0, tentacles inflected, most of which, after a few hours, 

 re-expanded, with the exception of No. 4, which retained its thirty- 

 two tentacles inflected for 48 hrs. 



Now for the eight corresponding leaves in water: 

 (1) After 2 hrs. 40 m. this had twenty of its outer tentacles 

 inflected, five of which re-expanded after 6 hrs. 30 m. After 10 

 hrs. 1.5 m. a most unusual circumstance occurred, namely, the 

 whole blade became slightly bowed towards the footstalk, and so 

 remained for 48 hrs. The exterior tentacles, excepting those of the 

 three or four outermost rows, were now also inflected to an unusual 

 degree. 



