Viola pratincola, Greene. A prairie species of the Middle West, from Ind. to Minn. and Colo.; like V. papilionacea, but less robust, and often united with that species: petals violet-purple but of a lighter shade than in No. 17, the petals broadly obovate. | Viola pratincola, Greene. A prairie species of the Middle West, from Ind. to Minn. and Colo.; like V. papilionacea, but less robust, and often united with that species: petals violet-purple but of a lighter shade than in No. 17, the petals broadly obovate. |