Much interest is still felt by keen observers of nature in the Yucca moth. It seems to be a certainty that except in a very few instances the common Yucca filamentosa bears no seed except when the Pronuba yucca-ella makes itself at home in the flowers. This we have said repeatedly to our readers. The insect deposits its eggs in the fruit, and the young fall out in the autumn, and remain for the winter in the ground. A couple of years ago Prof. Riley discovered another species of Yucca moth, which he calls Prodoxus decipiens. These deposit in the yucca stems, in which they remain all winter. The insects are so much alike as to appear the same to the unaided eye, and they associate together. In the early flowering species Yucca angustifolia, on the grounds of the Editor, seventeen insects caught in one flower, proved to be thirteen Pronuba and four Prodoxus. It is believed these insects were in the past ages of one type, and that it is a striking instance of distinct genera being derived at no very remote period from one stock.