In Can. Ent., vii., p. 236-240, I gave an account of experiments with P. Ajax, placing the chrysalids on ice. In vol. ix., 4 and 203, of Ajax, P. Tharos and L. Pseudargiolus. In Psyche, iii., 6 and 15, these were all brought together, and additional observations on G. Interrogationis were given; also p. 174, on L. Disippus. In the case of the seasonally-dimorphic Ajax, the conclusion was reached, Psyche, iii., 18, that the longer the exposure the more decided the change, but changes had been produced at 11 to 30 days; at and under 8 days no change was perceptible. That 30° to 40° Far. seemed to be the proper temperature for the purpose. That the effect of the cold was to albinize the butterfly, the black area being constantly reduced.