222 DROSERA ROTUNDIFOLIA. Ounapr. 1X. 
A plant was exposed in the same vessel to the gas for 45 m., and 
bits of meat were then placed on four glands. But the ten- 
tacles did not move for 1 hr. 40 m.; after 2 hrs. 30 m. all four 
were well inflected, and after 3 hrs. reached the centre. 
The following singular phenomenon sometimes, but by no 
means always, occurred. A plant was immersed for 2 hrs., and 
bits of meat were then placed on several glands. In the course 
of 13 m. aii the submarginal tentacles on one leaf became con- 
siderably inflected; those with the meat not in the least degree 
more than the others. On a second leaf, which was rather 
old, the tentacles with meat, as well as a few others, were 
moderately inflected. On a third leaf all the tentacles were 
closely inflected, though meat had not been placed on any of 
the glands. This movement, I presume, may be attributed to 
excitement from the absorption of oxygen. The last-mentioned 
leaf, to which no meat had been given, was fully re-expanded 
after 24 hrs.; whereas the two other leaves had all their ten- 
tacles closely inflected over the bits of meat which by this time 
had been carried to their centres. Thus these three leaves 
had perfectly recovered from the effects of the gas in the course 
of 24 hrs. 
On another occasion some fine plants, after having been left 
for 2 hrs. in the gas, were immediately given bits of meat in the 
usual manner, and on their exposure to the air most of their 
tentacles became in 12 m. curved into a vertical or sub-vertical 
position, but in an extremely irregular manner ; some only on one 
side of the leaf and some on the other. They remained in this 
position for some time; the tentacles with the bits of meat not 
having at first moved more quickly or farther inwards than the 
others without meat. But after 2 hrs. 20 m. the former began 
to move, and steadily went on bending until they reached the 
centre. Next morning, after 22 hrs., all the tentacles on these 
leaves were closely clasped over the meat which had been carried 
to their centres; whilst the vertical and sub-vertical tentacles on 
the other leaves to which no meat had been given had fully 
re-expanded. Judging, however, from the subsequent action of 
a weak solution of carbonate of ammonia on one of these latter 
leaves, it had not perfectly recovered its excitability and power 
of movement in 22 hrs.; but another leaf, after an additional 
24 hrs., had completely recovered, judging from the manner in 
which it clasped a fly placed on its disc. 
I will give only one other experiment. After the exposure of 
a piant for 2 hrs. to the gas, one of its leaves was immersed in 
a rather strong solution of carbonate of ammonia, together witk 
