Cuar. IX.] CAMPHOR. 171 
occasion, however, after a longer immersion of 24 hrs., there was well- 
marked aggregation. A solution made by adding two drops of campho- 
rated spirits to an ounce of water did not act on one leaf; whereas 
thirty minims added to an ounce of water acted on two leaves immersed 
together. - 
S j | Length of 
Z | Length of | | Time between 
~ | ae the Immersion 
s Immersion A Length of Time between the Act of Brushing | of the Leaves 
8 | the Solution | and the Inflection of the Tentacles. peg EE 
£ | of Camphor. | Sign of the 
is | | Inflection of the 
: | | Tentacles. 
1 i 3m. considerable inflection; 4 m. all e 
Pin t the tentacles except 3 or 4 inflected. : 
2 5m. | 6 m. first sign of inflection. | 11 m. 
6 m. 30 s. slight inflection; 7 m. 398.) 41 m. 30s. 
a k 
Co ico Tis Pee | . } 
{ plain inflection. | 
x 2 m. 30 s.a trace of inflection; 3 m. A 
4 4m.30s. i 7m, 
plain ; 4 m. strongly marked. 
(9 2 ý Ps tan: R 
2 m. 30 s. a trace of inflection m. : ? 
5 4m. Heir z - F | 6m. 30s. 
plain inflection. j 
2 m. 30 s. decided inflection; 3 m. 50 s. ; 30 ¢ 
6 4m . é 6 m. 30 s. 
strongly marked. 
. 2 m. 30 s. slight inflection; 3 m. plain;) ș& aN a 
7 4m. f eee >m. 30 s. 
4 m. well marked. Í 
8 2 (2 m. trace of inflection; 3 m. consider-) 5m 
3 m. : : 5 5m. 
, \ able, 6 m. strong inflection. 
2m. trace of inflection; 3 m. consider-) - 
9 3 m. ; : ae om. 
able, 6 m. strong inflection. 
M. Vogel has shown* that the flowers of various plants do not 
wither so soon when their stems are placed in a solution of camphor 
as when in water; and that if already slightly withered, they recover 
more quickly. The germination of certain seeds is also accelerated by 
the solution. So that camphor acts as a stimulant, and it is the only 
known stimulant for plants. I wished, therefore, to ascertain whether 
camphor would render the leaves of Drosera more sensitive to 
mechanical irritation than they naturally are, Six leaves were left in 
distilled water for 5 m. or 6 m., and then gently brushed twice or 
thrice, whilst still under water, with a soft camel-hair brush; but no 
movement ensued. Nine leaves, which had been immersed in the 
above solution of camphor for the times stated in the above table, 
* <Gardener’s Chronicle,’ 1874, p. 671. Nearly similar observations were 
made in 1798 by B. S. Barton. 
