seven leaves were so much doubled over that their tips and bases almost
touched. On no other occasion have I seen the blades so strongly
affected. Three leaves were also immersed, each in thirty minims of a
solution of one part to 875 of water; after 30 m. there was much
inflection, and after 6 hrs. 35 m. the blades of two and the tentacles
of all were closely inflected.
Sodium, Chloride of (best culinary salt). Half-minims of a solution of
one part to 218 of water were placed on the discs [page 178] of four
leaves. Two, apparently, were not at all affected in 48 hrs.; the third
had its tentacles slightly inflected; whilst the fourth had almost all
its tentacles inflected in 24 hrs., and these did not begin to
re-expand until the fourth day, and were not perfectly expanded on the
seventh day. I presume that this leaf was injured by the salt.
Half-minims of a weaker solution, of one part to 437 of water, were
then dropped on the discs of six leaves, so that each received 1/960 of
a grain. In 1 hr. 33 m. there was slight inflection; and after 5 hrs.
30 m. the tentacles of all six leaves were considerably, but not
closely, inflected. After 23 hrs. 15 m. all had completely re-expanded,
and did not appear in the least injured.
Three leaves were immersed, each in thirty minims of a solution of one
part to 875 of water, so that each received 1/32 of a grain, or 2.02
mg. After 1 hr. there was much inflection; after 8 hrs. 30 m. all the
tentacles and the blades of all three were closely inflected. Four
other leaves were also immersed in the solution, each receiving the
same amount of salt as before, viz. 1/32 of a grain. They all soon
became inflected; after 48 hrs. they began to re-expand, and appeared
quite uninjured, though the solution was sufficiently strong to taste
saline.
Sodium, Iodide of. Half-minims of a solution of one part to 437 of
water were placed on the discs of six leaves. After 24 hrs. four of
them had their blades and many tentacles inflected. The other two had
only their submarginal tentacles inflected; the outer ones in most of
the leaves being but little affected. After 46 hrs. the leaves had
nearly re-expanded. Three leaves were also immersed, each in thirty
minims of a solution of one part to 875 of water. After 6 hrs. 30 m.
almost all the tentacles, and the blade of one leaf, were closely
inflected.
159