CONTRIBUTIONS to our knowledge on the role of neuroendocrine mechanisms in the regulation of sexual behavior in mammals have been carefully summarized and evaluated in two excellent reviews by Beach.* It is generally agreed that copulatory behavior of adult males of several subprimate species can be diminished by castration or by injury of the central nervous system. The observations of Beach and Zitrin† indicate that extensive but incomplete destruction of the neocortex markedly interferes with the coordination of sensorymotor components of coital behavior in male cats. After complete neodecortication their cats failed to exhibit sexual interest or overt patterns of mating behavior when placed in association with receptive females. From these findings it would seem that the neopallium of this male carnivore, in addition to contributing sensory-motor components, exerts a generalized facilitative influence upon subcortical structures involved in the mediation of sexual behavior. In addition to contributions from the neopallium,