re-expanded.
Of the four corresponding leaves in water:
(1) After 1 hr. forty-five tentacles inflected; but after 7 hrs. so
many had re-expanded that only ten remained much inflected.
(2) After 1 hr. seven tentacles inflected; these were almost
re-expanded in 6 hrs.
(3) and (4) Not affected, except that, as usual, after 11 hrs. the
short tentacles on the borders of the disc formed a ring.
There can, therefore, be no doubt about the efficiency of the above
solution; and it follows as before that each gland of No. 1 could have
absorbed only 1/2412000 of a grain (.0000268 mg.) and of No. 2 only
1/2460000 of a grain (.0000263 mg.) of the phosphate.
Seven leaves were immersed, each in thirty minims of a solution of one
part to 437,500 of water (1 gr. to 1000 oz.). Each leaf thus received
1/16000 of a grain (.00405 mg.). The day was warm, and the leaves were
very fine, so that all circumstances were favourable.
(1) After 30 m. all the outer tentacles except five inflected, and most
of them closely; after 1 hr. blade slightly inflected; after 9 hrs. 30
m. began to re-expand.
(2) After 33 m. all the outer tentacles but twenty-five inflected, and
blade slightly so; after 1 hr. 30 m. blade strongly inflected and
remained so for 24 hrs.; but some of the tentacles had then
re-expanded.
(3) After 1 hr. all but twelve tentacles inflected; after 2 hrs. 30 m.
all but nine inflected; and of the inflected tentacles all excepting
four closely; blade slightly inflected. After 8 hrs. blade quite
doubled up, and now all the tentacles excepting [page 162] eight
closely inflected. The leaf remained in this state for two days.
(4) After 2 hrs. 20 m. only fifty-nine tentacles inflected; but after 5
hrs. all the tentacles closely inflected excepting two which were not
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