CuAP. VII.] PHOSPHATE OP AMMONIA. I33 



leaves were not more affected after 12 hrs. than the four corre- 

 sponding ones in water; but after 24 lirs. tliey were sliglitly more 

 intiected. Such evidence, however, is not at all trustworthy. 



Twelve leaves were immersed, each in thirty minims of a solu- 

 tion of one part to 1,312,500 of water (1 gr. to 3000 oz.); so that 

 each leaf received xahrs of a grain (.00135 mg.). The leaves were 

 not in very good condition; four of them were too old and of a 

 dark red colour; four were too pale, yet one of these latter acted 

 well ; the four others, as far as could be told by the eye, seemed in 

 excellent condition. The result was as follows: 



(1) This was a pale leaf; after 40 m. about thirty-eight tenta- 

 cles inflected; after 3 hrs. 30 m. the blade and many of the outer 

 tentacles inflected; after 10 hrs. 15 m. all the tentacles but seven- 

 teen inflected, and the blade quite doubled up; after 24 hrs. all 

 the tentacles but ten more or less inflected, ilost of them were 

 closely inflected, but twenty-five were only sub-inflected. 



(2) After 1 hr. 40 m. twenty-five tentacles inflected; after 6 

 hrs. all but twenty-one inflected; after 10 hrs. all but sixteen more 

 or less inflected ; after 24 hrs. re-expanded. 



(3) After 1 hr. 40 m. thirty-five inflected; after 6 hrs. "a 

 large number" (to quote my own memorandum) inflected, but 

 from want of time they were not counted; after 24 hrs. re- 

 expanded. 



(4) After 1 hr. 40 m. about thirty infleete<l; after 6 hrs. "a 

 large number all round the leaf " inflected, but they were not 

 counted; after 10 hrs. began to re-expand. 



(5) to (12) These were not more inflected than leaves often 

 are in water, having respectively 10, 8, 10, 8, 4, 9, 14, and tenta- 

 cles inflected. Two of these leaves, however, were remarkable from 

 having their blades slightly inflected after G hrs. 



With respect to the twelve corresponding leaves in water, (I) 

 had, after 1 hr. 35 m., fifty tentacles inflected, but after 11 hrs. only 

 twenty-two remained so, and these formed a group, with the -blade 

 at this point slightly inflected. It appeared as if this leaf had been 

 in some manner accidentally excited, for instance by a particle of 

 animal matter wliich was dissolved by the water. (2) After 1 hr. 

 45 m. thirty-two tentacles inflected, but after 5 hrs. 30 m. 

 only twenty-five inflected, and these after 10 hrs. all re-ex- 

 panded; (3) after 1 hr. twenty-five inflected, which after 10 hrs. 

 20 m. were all re-expanded; (4) and (5) after 1 hr. 35 m. six and 

 seven tentacles inflected, which re-expanded after 11 hrs.; (6), (7) 

 and (8) from one to three inflected, which soon re-expanded; (0), 

 (10), (11) and (12) none inflected, though observed for 24 hrs. 



Comparing the states of the twelve leaves in water with those 

 in the solution, there could be no doubt that in the latter a larger 

 number of tentacles were inflected, and these to a greater degree; 

 but the evidence was by no means so clear as in the former ex- 

 periments with stronger solutions. It deserves attention that the 

 inflection of four of the leaves in the solution went on increasing 

 during the first G hrs., and with some of them for a longer time; 



