A study of the spring migration movements of the spotted salamander, A. maculatum (Shaw), at Ann Arbor, Michigan, during 1924, 1926, and 1927 has shown a lack of correlation with the air temp. but a very marked correlation with the incidence of rainfall at night. It was concluded that the salamanders move toward the breeding ponds only at night and only during a rain, that migration begins on the first rainy night following disappearance of the snow and thawing of the surface of the ground, and that a prolonged rain, or several rains, are required to bring all adult individuals of any given locality to the breeding sites. The data published earlier by Wright and Allen, from which the conclusion was drawn that temp. is the primary factor in the spring migration of this sp., are shown, by comparison with the precipitation records for those periods, to support instead the present rainfall theory.