Abstract
The mesencephalon is an important integrating center in lower vertebrate. Motor function of the mesencephalon (optic lobe) in Amphibia was examined by Abbie and Miyazawa, and the motor control of it, is confirmed to be bilateral in Bufo. In the present report, the tonic continous action of optic lobe upon the spinal cord was examined.
By excision of one side of optic lobes, the ipsilateral reflex is at first inhibited slightly, but later the both sides of spinal reflexes are exceedingly augmented.
By excision of both sides of optic lobes, the spinal reflexes diminished by and by. Such experimental facts show that the optic lobes are acting continously to inhibit the spinal cord, but its mechanism is considerably complex.
