The flowering behavior of four spring-blooming herbs having a wide distribution throughout the eastern United States was observed in a uniform environment. Throughout the summer and fall these plants were kept outside in cold frames in a Smith College garden. In January 1966 and 1967, the plants were transferred from outside into a greenhouse with an average daily temperature of 60°F. and an average night temperature of 50°F. Three types of flowering behavior were observed. Viola papilionacea and Saxifraga virginiensis show evidence of distinct race formation. Hepatica americana also shows evidence of race formation. However, in the uniform garden the flowering behavior of this species was altered by the total light hours received. Sanguinaria canadensis shows no evidence of race formation. It apparently responds directly to favorable environmental conditions.