Carrying the Analysis Back to the Lowly Prehistoric Clam. Laughter is an involuntary physical tion. Hughlings Jackson calls it e of the innumerable epilepsies to which man is subject.” It is apparent ly a universal heritage, though certain causes may operate more powerfully upon one individual than upon another to produce it. In the little child whose sensibilities are uncomplicated by any @otal experience unless they be racial by the shock of delicate touch—tick Lea as we call it—first causes laugh . Why? “the claim of our psychologist carries us a long leap backward to the most _elemental form of animal life. Beyond the savage stands the monkey and firmly far beyond him the mollusk, whose only sense was that of touch. Picture this great-grandfather,of liv ing things lying motionless save for those nervous,fluttering, sensitive feel ers extend. Play the part of sight and hearing: bit of seaweed bumps against them. A spasm racks the mol lusk’s whole being, crushing him into his shell until the surprise has abated; then the fact that no farther attack bollows brings relief. As the germ of the cause of our laughter spasm—a sudden shock, in stantly followed by a feeling of relief. Only such shocks as were followed by relief became racial memories. Where relief did not follow the dam did not live to leave a heritage.—Burges John sson in Harper's Magazine,