Cuar. VIII. THE EFFECTS OF ACIDS. 195 
tentacles were somewhat inflected, and all the glands very pale- 
coloured; the surrounding fluid was coloured pink. On one 
occasion the-fluid became pink in the course of only 12m., and 
the glands as white as if the leaf had been dipped in boiling 
water. After 4 hrs. much inflection; but none of the tentacles 
were closely inflected, owing, as I believe, to their having been 
paralysed before they had time to complete their movement. 
An extraordinary quantity of mucus was secreted. Some of the 
leaves were left in the solution; others, after an immersion of 
6 hrs. 30 m., were placed in water. Next morning both lots 
were quite dead; the leaves in the solution being flaccid, those 
in the water (now coloured yellow) of a pale brown tint, and 
their glands white. ; 
Succinic Acid.—Three leaves were immersed in ninety minims 
of a solution of 1 gr. to 437 of water; after 4 hrs. 15 m. consider- 
able and after 23 hrs. great inflection; many of the glands 
pale; fluid coloured pink. The leaves were then washed and 
placed in water; after two days there was some re-expansion, 
but many of the glands were still white. This acid is not 
nearly so poisonous as oxalic or benzoic. 
Uric Acid.—Three leaves were immersed in 180 minims of a 
solution of 1 gr. to 875 of warm water, but all the acid was not 
dissolved; so that each received nearly ~, of a grain. After 
25 m. there was some slight inflection, but this never increased ; 
after 9 hrs. the glands were not discoloured, nor was the solu- 
tion coloured pink; nevertheless much mucus was secreted. 
The leaves were then placed in water, and by next morning 
fully re-expanded. I doubt whether this acid really causes 
inflection, for the slight movement which at first occurred may 
lave been due to the presence of a trace of albuminous matter. 
But it produces some effect, as shown by the secretion of so 
much mucus. 
Hippuric Acid.—Four leaves were immersed in 120 minims of 
a solution of 1 gr. to 487 of water. After 2 hrs. the fluid was 
coloured pink; glands pale, but no inflection. After 6 hrs. some 
inflection; after 9 hrs. all four leaves greatly inflected: much 
mucus secreted; all the glands very pale. The leaves were then 
left in water for two days; they remained closely inflected, 
with their glands colourless, and I do not doubt were Pitted. 
Hydrocyanic Acid.—Four leaves were immersed, each in thirty 
minims of one part to 437 of water; in 2 hrs. 45 m. all the 
tentacles were considerably inflected, with many of the glands 
pale; after 3 hrs. 45 m. all stronyly inflected, and the surround- 
ing fluid coloured pink; after 6 hrs. all closely inflected. After 
