Cuap. IX. ALKALOID POISONS. 201 
of two other leaves, after an immersion for 2 hrs. in a stronger 
solution, of one part of the citrate to 218 of water, became of an 
opaque, pale pink colour, which before long disappeared, leaving 
them white. One of these two leaves had its blade and 
tentacles greatly inflected; the other hardly at all; but the 
protoplasm in the cells of both was aggregated down to the 
bases of the tentacles, with the spherical masses in the cells 
close beneath the glands blackened. After 24 hrs. one of these 
leaves was colourless, and evidently dead. 
Sulphate of Quinine—Some of this salt was added to 
water, which is said to dissolve z)55 part of its weight. 
Five leaves were immersed, each in thirty minims of this solu- 
tion, which tasted bitter. In dess than 1 hr. some of them had 
a few tentacles inflected. In 3 hrs. most of the glands became 
whitish, others dark-coloured, and many oddly mottled. After 
6 hrs. two of the leaves had a good many tentacles inflected, but 
this very moderate degree of inflection never increased. One of 
the leaves was taken out of the solution after 4 hrs., and placed 
in water; by the next morning some few of the inflected 
tentacles had re-expanded, showing that they were not dead; 
but the glands were still much discoloured. Another leaf not 
included in the above lot, after an immersion of 3 hrs. 15 m., 
was carefully examined; the protoplasm in the cells of the 
outer tentacles, and of the short green ones on the disc, had 
become strongly aggregated down to their bases; and I distinctly 
saw that the little masses changed their positions and shapes 
rather rapidly ; some coalescing and again separating. I was 
surprised at this fact, because quinine is said to arrest all move- 
ment in the white corpuscles of the blood ; but as, according to 
Binz,* this is due to their being no longer supplied with oxygen 
by the red corpuscles, any such arrestment of movement could 
not be expected in Drosera. That the glands had absorbed some 
of the salt was evident from their change of colour; but I at 
first thought that the solution might not have travelled down 
the cells of the tentacles, where the protoplasm was seen in 
active movement. This view, however, I have no doubt, is 
erroneous, for a leaf which had been immersed for 3 hrs. in the 
quinine solution was then placed in a little solution of one part of 
carbonate of ammonia to 218 of water; and in 30 m. the glands 
and the upper cells of the tentacles became intensely black, with 
the protoplasm presenting a very unusual appearance; for it 
* ‘Quarterly Journal of Microscopical ¥cience,’ April 1874, p. 185. 
