162 DROSERA ROTUNDIFOLIA. [Cuar. IX, 
CHAPTER IX. 
Tne EFFECTS OF CERTAIN ALKALOID PoIsoNs, OTHER SUBSTANCES AND 
Varovrs, 
Strychnine, salts of—Qiunine, sulphate of, does not soon arrest the move- 
ment of the protoplasm—Other salts of quinine—Digitaline—Nicotine— 
Atropine — Veratrine — Colchicine — Theine — Curare—Morphia—Hyos- 
cyamus—Poison of the cobra, apparently accelerates the movements of 
the protoplasm—Camphor, a powerful stimulant, its vapour narcotic— 
Certain essential oils excite movement—Glycerine—Water and certain 
solutions retard or prevent the subsequent action of phosphate of 
ammonia—Alcohol innocuous, its vapour narcotic and poisonous—Chloro- 
form, sulphuric and nitric ether, their stimulant, poisonous, and narcotic 
power—Carhonic acid narcotic, not quickly poisonous — Concluding 
remarks, 
As in the last chapter, I will first give my experiments and 
then a brief summary of the results with some concluding 
remarks. 
Acetate of Strychnine—Half-minims of a solution of one part to 437 
of water were placed on the discs of six leaves; so that each received 
sta of a grain, or *0675 mg. In 2 hrs. 30 m. the outer tentacles on 
some of them were inflected, but in an irregular manner, sometimes 
only on one side of the leaf. The next morning, after 22 hrs. 30 m., 
the inflection had not increased. ‘The glands on the central disc were 
blackened, and had ceased secreting. After an additional 24 hrs. all 
the central glands seemed dead, but the inflected tentacles had re-ex- 
panded and appeared quite healthy. Hence the poisonous action of 
strychnine seems confined to the glands which have absorbed it; never- 
theless, these glands transmit a motor impulse to the exterior tentacles. 
Minute drops (about ; of a minim) of the same solution applied to 
the glands of the outer tentacles occasionally caused them to bend. 
The poison does not seem to act quickly, for having applied to several 
glands similar drops of a rather stronger solution, of one part to 292 of 
water, this did not prevent the tentacles bending, when their glands 
were excited, after an interval of a quarter to three quarters of an hour, 
-by being rubbed or given bits of meat. Similar drops of a solution of 
one part to 218 of water (2 grs. to 1 oz.) quickly blackened the glands ; 
some few tentacles thus treated moved, whilst others did not. The 
