Chap. VII. OTHER SALTS OF AMMONIA. 167 



becoming more inflected. After 23 hrs. three of tlie leaves had 

 tlieir blades somewhat inflected ; and the submarginal tentacles 

 of all considerably inflected, but in none were the two, three, or 

 four outer rows affected. I have rarely seen cases like this, 

 except from the action of a decoction of grass. The glands on the 

 discs of the above leaves, instead of being almost black, as after 

 the first hour, were now after 23 hrs. very pale. I next tried 

 on four leaves half-minims of a weaker solution, of one part to 

 1312 of water (1 gr. to 3 oz.) ; so that each received ^^^ of 

 a grain (-0225 mg.). After 2 hrs. 18 m. the glands on the disc 

 were very dark-coloured ; after 21 hrs. two of the leaves were 

 slightly affected ; the other two not at all. 



Acetate of Ammonia. — Half-minims of a solution of ahout one 

 part to 109 of water were placed on the -discs of two leaves, both 

 of which were acted on in 5 hrs. 30 m., and after 23 hrs. had 

 every single tentacle closely inflected. 



Oxalate of Ammonia. — Half-minims of a solution of one part 

 to 218 of water were placed on two leaves, which, after 7 hrs., 

 became moderately, and after 23 hrs. strongly, inflected. Two 

 other leaves were tried with a weaker solution of one part 

 to 437 of water ; one was strongly inflected in 7 hrs. ; the other 

 not until 30 hrs. had elapsed. 



Tartrate of Ammonia. — Half-minims of a solution of one part 

 to 437 of water were placed on the discs of five leaves. In 

 31 m. there was a trace of inflection in the exterior tentacles of 

 some of the leaves, and this became more decided after 1 hr. 

 with all the leaves; but the tentacles were never closely in- 

 flected. After 8 hrs. 30 m. they began to re-expand. Next 

 morning, after 23 hrs., all were fully re-expanded, excepting 

 one which was still slightly inflected. The shortness of the 

 period of inflection in this and the following case is remark- 

 able. 



Chloride of Ammonium. — Half-minims' of a solution of one 

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

 A decided degree of inflection in the outer and. submarginal 

 tentacles was perceptible in 25 m. ; and this increased during 

 the next three or four hours, but never became strongly marked. 

 After only 8 hrs. 30 m. the tentacles began to re-expand, and 

 by the next morning, after 24 hrs., were fully re-expanded on 

 four of the leaves, but still slightly inflected on two. 



General Summary and Concluding BemarJcs on the 

 Salts of Ammonia. — We have now seen that the nine 



