Qnap. IX. SUMMARY OF THE CHAPTER. 225 
Of the alkaloids and their salts which were tried, 
several had not the least power of inducing inflection ; 
others, which were certainly absorbed, as shown by the 
changed colour of the glands, had but a very mode- 
tate power of this kind; others, again, such as the 
acetate of quinine and digitaline, caused strong in- 
flection. 
The several substances mentioned in this chapter 
affect the colour of the glands very differently. These 
often become dark at first, and then very pale or 
white, as was conspicuously the case with glands 
subjected to the poison of the cobra and citrate of 
strychnine. In other .cases they are from the first 
rendered white, as with leaves placed in hot water and 
several acids; and this, I presume, is the result of the 
coagulation of the albumen. On the same leaf some 
glands become white and others dark-coloured, as 
occurred with leaves in a solution of the sulphate of 
quinine, and in the vapour of alcohol. Prolonged im- 
mersion in nicotine, curare, and even water, blackens 
the glands; and this, I believe, is due to the agere- 
gation of the protoplasm within their cells, Yet 
curare caused very little aggregation in the cells of 
the tentacles, whereas nicotine and sulphate of quinine 
induced strongly marked aggregation down their 
bases. The aggregated masses in leaves which had 
been immersed for 3 hrs. 15 m. in a saturated solu- 
tion of sulphate of quinine exhibited incessant 
it is remarkable that Dr. Ransom 
(¢Philosoph. Transact.’ 1867, p. 
480), who used much stronger 
solutions of these substances than 
I did, states “that the rhythmic 
contractility of the yolk (of the 
ova of the pike) is not materially 
influenced by any of the poisons 
used, which did not act chemi- 
cally, with the exception of chloro- 
form and carbonic acid.” I find 
it stated by several writers that 
curare has no influence on sarcode 
or protoplasm, and we have seen 
that, though curare excites some 
degree of inflection, it causes very 
little aggregation of the proto- 
plasm. 
