Note 33 — Chapter III · OCCASIONS AND CAUSES OF LAUGHTER.
Reading edition
See the article on “The Psychology of Tickling, Laughing, and the Comic,” by G. S. Hall and A. Allin, in the American Journal of Psychology, vol. ix., p. 1 ff. These returns do not make it quite clear whether “ticklishness” is taken to mean the non-laughing as well as the laughing varieties.