176 DROSEEA EOTUNDIFOLIA. Ch^p. Vm. 



Sodium, Carbonate of (pure, given me by Prof. Hoflfmann). — 

 Half-minims ("0296 ml.) of a solution of one part to 218 of 

 ■water (2 grs. to 1 oz.) were placed on the discs of twelve leaves. 

 Seven of these became well inflected; three had only two or 

 tliree of their outer tentacles inflected, and the remaining two 

 were quite unafiected. But the dose, though only the ^^ of a 

 grain {'13b mg.), was evidently too strong, for thi-ee of the 

 seven well-inflected leaves were kiUed. On the other hand, one 

 of the seven, which had only, a few tentacles inflected, re- 

 expanded and seemed quite healthy after 48 hrs. By employing 

 a weaker solution (viz. one part to 437 of water, or 1 gr. to 

 1 oz.), doses of 9^0 of a grain ('0075 mg.) were given to six 

 leaves. Some of these were affected in 37 m. ; and in 8 hrs. the 

 outer tentacles of all, as well as the blades of two, were con- 

 siderably inflected. After 23 hi's. 15 m. the tentacles had 

 almost re-expanded, but the blades of the two were still just 

 perceptibly curved inwards. After 48 hrs. all six leaves were 

 fully re-expanded, and appeared perfectly healthy. 



Three leaves were immersed, each in thii'ty minims of a solu- 

 tion of one part to 875 of water (1 gr. to 2 oz.), so that each 

 received gV of a grain (2-02 mg.); after 40 m. the three wero 

 much afl'ected, and after 6 hrs. 45 m. the tentacles of all and 

 the blade of one closely inflected. 



Sodium, Nitrate of (pure).— Half-minims of a solution of one 

 part to 437 of water, containing g^ of a grain (-0675 mg.), 

 were placed on the discs of five leaves. After 1 hr. 25 m. tho 

 tentacles of nearly all, and the blade of one, were somewhat 

 inflected. The imQection continued to increase, and in 21 hi'S. 

 15 m. the tentacles and the blades of four of them were greatly 

 aflected, and the blade of the fifth to a slight extent. After an 

 additional 24 hrs. the four leaves still remained closely inflected, 

 whilst the fifth was beginning to expand. Four days after tho 

 solution had been applied, two of the leaves had quite, and ono 

 liad partially, re-expanded ; whilst the remaining two remained 

 closely inflected and appeared injiu-ed. 



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

 tion of one part to 875 of water ; in 1 hr. there was great inflec- 

 tion, and after S hrs. 15 m. every tentacle and the blades of all 

 thi-ee were most strongly inflected. 



Sodium, Sulphate of — Half-minims of a solution of one part 

 to 437 of water were placed on the discs of six leaves. After 

 5 hrs. 30 m. the tentacles of three of them (with the blade of 

 one) were considerably, and those of the other three slightly, 

 inflected. After 21 hi's. the inflection had a little decreased. 



