was left, and actually succeeded in removing the acid. Pflüger was so astonished and impressed by his experiment that he declared the spinal cord to be possessed of sensory powers—that is, capable of consciousness. I have stated this experiment in detail because it is the most striking among the many facts which have led to such a conclusion as that of Dr. Hammond in his address at Lehigh University, in October of last year. The address may be found in the November number of "The Popular Science Monthly." Dr. Hammond writes, "Suffice it to say that these experiments all go to establish the fact that the spinal cord, after the complete removal of the brain, has the
Fig. 9.—Inferior Surface of the Cerebellum. (Sappey, after Hirschfeld.) 1, 1, inferior vermiform process; 2, 2, median fissure of the cerebellum; 3, 3, 3, lobes and lobules of the cerebellar hemispheres; 4, "amygdala," or almond-like lobe; 5, lobule of the pneumogastric; 6, pons Varolii; 7, median groove on the same; 8, middle peduncle of the cerebellum; 9, cut surface of medulla; 10, anterior extremity of the great circumferential fissure; 11, anterior border of the upper surface of the cerebellum; 12, motor rout of the trigeminal nerve; 13, sensory root of the same; 14, nerve of the external ocular muscle; 15, facial nerve; 16, nerve of Wrisberg; 17, auditory nerve; 18, glosso-pharyngeal nerve; 19, pneumogastric nerve; 20, spinal accessory nerve; 21, hypoglossal nerve.
power of perception and volition, and that the actions performed are to all intents and purposes as perfect of their kind as they would be were the brain in its place." Though Dr. Hammond does not mention Pflüger's experiment, he cites other instances to the same effect. He has seen "the headless body of the rattlesnake coil itself into a threatening attitude, and, when irritated, strike its bleeding trunk against the offending body." Perrault reports that "a viper whose head had been cut off moved determinedly toward its hole in the wall." Neither these instances, nor the others which Dr. Hammond names in this connection, are as striking as Pflüger's experiment. The noticeable feature in this experiment is the fact that the muscular movements which appear upon irritation of the afferent fibers seem not merely to display a general conformity to ends, but to adjust themselves to changed conditions. Lotze, remembering the involuntary course of acquired movements in man, says, "These actions which point to a consciousness may be simply the back-workings of consciousness upon the mechanism of the reflex organ." Wundt thinks that, "if with Darwin we
