In certain parts of the valley of the Rio Pastaza, Ecuador, this butterfly approaches being an economic pest. With the introduction of small farms in the less arid portions of the temperate region of the valley it has adopted "zanahoria blanca", the white carrot, as its favored food plant. One day last week a native collector. Segundo Velastique, brought me ninety-two larvae in the last three instars. Descriptions of these and of the chrysalis follow.