excitatory physiological reaction is, as we know, abolished temporarily by the action of excessive cold.
This intervention of an excitatory, stimulating, or liberating energy is universal.
I have shown that the midday closure of leaflets is brought about by the excitatory action of strong sunlight.
The excitatory movement will now be the erection of the petiole, against gravity.
According to this view the excitatory fall of the leaf is a passive, rather than an active, movement.
The excitatory reaction of the upper half is by contraction, and the response is, therefore, the lifting of the petiole.
There is a responsive reaction which is opposite to the excitatory change described above.
The conduction of excitation consists, on the other hand, of propagation of excitatory protoplasmic change.
The upper side of a horizontally laid shoot is found to undergo an excitatory change of galvanometric negativity.
In the present case, the velocity of the excitatory negative impulse is 1.1 mm.