Just what induces a plant to become variegated is still a mystery. Mr. Rupp, the famous improver of the Chinese Primrose, tried in vain everything he could think of to produce variegation in the leaves. At length, noting a variegated plant of the common clover in the fields, the thought struck him that possibly there might be some condition of the soil which induced it. He took the soil about this clover plant, put some in a pot with a seedling primrose, and got his long desired variegation. "One swallow does not make a summer." Perhaps so, but it is worth looking out for more when we see one.