The intrinsic innervation of the penises of Galago and Tupaia were studied using modern histochemical techniques. The adrenergic and cholinergic innervation of the penile vessels and intrinsic musculature in these two species were similar. However, the adrenergic nerves of Tupaia were more intensely fluorescent than in Galago. The possibility of an efferent component of the dorsal nerve of the penis is discussed.