1. In this paper exploratory experiments have been described in which some oxidized indole derivatives have stimulated slightly the growth of corn coleoptile sections. 2. When potassium indoxyl sulfate and indoxyl acetate were supplied, light appeared to modify greatly the growth response. 3. Whether considered as degradation products in the metabolism of IAA or as distinct biological entities, these derivatives seem worthy of more extensive study. The lability and the light sensitivity of the compounds suggest a possible biochemical role for them in the response of tissues to light.