150 DROSERA ROTUNDIFOLIA. [Chap. VIII. 



closely inflected. It appears that the nitrate of strontium renders 

 the leaves hiilf torpid. 



Cadmiuin, Chloride of. Three leaves were immersed in ninety 

 minims of a solution of one part to 437 of water; after 5 hrs. 20 m. 

 slight inflei'tion occurred, which increased during the next three 

 hours. After 24 hrs. all three leaves had their tentacles well in- 

 flected, and remained so for an additional 24 hrs.; glands nut 

 discoloured. 



Mercury, Pcrchloride of. Three leaves were immersed in 

 ninety minims of a solution of one part to 437 of water; after 

 22 m. there was some sliglit inflection, which in 48 m. became well 

 pronounced; the glands were now blackened. After 5 hrs. 35 m. all , 

 the tentacles closely inflected; after 24 hrs. still inflected and dis- 

 coloured. The leaves were then removed and left for two days 

 in water; but they never re-expanded, being evidently dead. 



Zinc, Chloride of. Three leaves immersed in ninety minims of 

 a solution of one part to 437 of water were not affected in 25 hrs. 

 30 m. 



Aluminium, Chloride of. Four leaves were immersed in 120 

 minims of a solution of one part to 437 of water; after 7 hrs. 45 m. 

 no inflection; after 24 hrs. one leaf rather closely, the second mod- 

 erately, the third and fourth hardly at all, inflected. The evidence 

 is doubtful, but I think some power in slowly causing inflection 

 must be attributed to this salt. Those leaves wore then placed in 

 the solution (1 gr. to 20 oz.) of phosphate of ammonia, and after 

 7 hrs. 30 m. the three, which had been but little affected by the 

 chloride, became rather closely inflected. 



Aluminium, }k'itrate of. Four leaves were immersed in 120 

 minims of a solution of one part to 437 of water; after 7 hrs. 45 m. 

 there was only a trace of inflection; after 24 hrs. one leaf was 

 moderately inflected. The evidence is here again doubtful, as in 

 the case of the chloride of aluminium. The leaves were then 

 transferred to the same solution as before, of phosphate of am- 

 monia; this produced hardly any effect in 7 hrs. 30 m. ; but after 

 25 hrs. one leaf was pretty closely inflected, the three others very 

 slightly, perhaps not more so than from water. 



Aluminium and Potassium, Sulphate of (common alum). 

 Half-minims of a solution of the iisual strength were placed on the 

 discs of nine leaves, but produce<l no effect. 



(Hold, Chloride of. Seven leaves were immer8e<l in so much of a 

 solution of one part to 437 of water that each received 30 minims, 

 containing A of a grain, or 4.048 mg., of the chloride. There was 

 some inflection in 8 m., which IxK-ame extreme in 45 m. In 3 hrs. 

 the surrounding fluid was coloured purple, and the glands were 

 blackened. After hrs. the leaves were transferroil to water; next 

 morning they were found discoloured and evidently killed. The 

 secretion decomposes the chloride very readily; the glands them- 

 selves becoming coated with the thinnest layer of metallic gold, 

 and particles float almut on the surface of the surrounding fluid. 



IjCad, Chloride of. Three loaves were immerswl in ninety min- 

 ims of a solution of one part to 437 of water. After 23 hrs. there 



