This idea may suggest to various observers an interesting point of view. When you see a butterfly flying leisurely from plant to plant and alighting upon the leaves rather than the blossom, you may be pretty sure that she is bent upon egg-laying. Now watch her to see if she goes at once to the particular kind of leaves she finally selects or does she stop momentarily upon neighboring plants, apparently trying to find the one from which the fragrance emanates until at last she reaches it. Such observations have only rarely been recorded and if carefully made, notes being taken on the spot, they would have decided scientific value. _Abundance and Distribution_ Few butterflies are more abundant or more widely distributed throughout North America than the beautiful little Pearl Crescent. It occurs over practically the whole of the United States and Canada and is found from early in spring until late in autumn. It is a rather small species with a wing expanse of only about an inch and a quarter, the upper surface of the wings being that tone of reddish brown called fulvous, more or less marked with black wavy lines and dots. The under surface is similar in color, with a small silver crescent near the outer margin of each hind wing. These butterflies are not very active creatures, although they are commonly found in meadows and pastures along brooks and by the borders of open woods. Instead of laying their eggs singly as do so many of the more active butterflies, they lay them in clusters, often of a hundred or more, one layer of eggs being placed above the other upon the aster leaf. In at least one case observed, the caterpillars hatch from the layer farthest away from the leaf surface before those of the layer next the leaf surface emerge. This is an interesting provision, for were the latter to come out first they would be likely to disarrange the unhatched eggs. The caterpillars appear about a week after the eggs are laid and remain together in crowded colonies that feed upon the upper surface of the aster leaf. At first they eat only the green tissue, leaving the bare veins, although they are not careful to denude the entire surface of the leaf as so many other caterpillars do. As one leaf is exhausted they pass to another near by, continuing thus to feed in companies for a few weeks. Their general color is blackish, although the black is relieved with yellow dots along the back and a band of a similar color on each side. Unlike the larger social caterpillars of the Mourning Cloak and other butterflies these larvae do not spin any threads as they crawl from place to place, so there is absolutely no nest made upon the aster leaf. This may possibly be correlated with the fact that these caterpillars are sluggish creatures and when disturbed drop quickly to the soil beneath.