On the 6th of June, 1868, we observed for the first time a handsome green caterpillar eating some lettuce that we rvere growing in our graper-v ; thinking that it could not very well escape, we merely took a rough description, as follows :–Sixteen-footed caterpillar, about an inch long, pale green (almost the colour of lettuce leaves) above, deeper green below; a white dorsal line, two lateral white lines, the lower passing through the spiracles ; all five lines proceeding from head to tail. Before we secured it, it did, however, escape, probably entering the ground.

The following year, in June and early in July, we observed many similar larvæ on a number of different plants, both in the garden and in the woods.