Cuayr. VIIL 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. 80 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 487 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 
luave 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 437 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 killed. 
Hydrocyanic Acid.—Four leaves were immersed, each in thirty 
minims of one part to 487 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 strongly inflected, and the surround- 
ing fluid coloured pink; after 6 hrs. all closely inflected. After 
