One would naturally suppose that when a butterfly was reduced to the greatest possible simplicity in its coloring there would be little chance for the development of geographical or seasonal varieties. But he would only have to study a large collection of specimens of this species, taken at different seasons and in different regions, to find his supposition at fault. Here is a butterfly which is essentially a slender black-bodied creature with four white wings scarcely touched with color, and yet we are told that there are eleven varieties in the United States so distinct that they have received scientific names, not to mention various others which have been found in Europe. This is indeed a remarkable showing and it is a striking illustration of the infinite variations which Nature can produce with the most limited materials. To me the seasonal variations of a butterfly are always of greater interest than those which are geographical. We know that in the case of a great many animals, from insects to mammals, the different conditions of climate and physical environment found in different regions produce variations of many sorts. So it does not seem especially strange that in Alaska there should be a different form of a certain butterfly than is found in Virginia. But that in the same locality there should be two or more forms of a butterfly existing under identical conditions as to climate and environment is not so easily explained. In the case of the Gray-veined White we collect in early spring in New England, or other Northern states, a lot of chrysalids. We keep them until the butterflies come forth and we find even here two distinct forms, one smaller and more delicate than the other, with both surfaces of the wings pure white: scientists call this form, _virginiensis_; the other larger with the under surface of the wings slightly tinted with yellow: scientists call this form _oleracea_. The first named has but one brood a year while the second lays eggs which develop into caterpillars that produce butterflies of still a _third_ form, in which the upper surface of the wings is pure white with a slightly greater expanse: scientists call this form _cruciferarum_. These three varieties occur in Eastern regions and may be found in the same localities, and differ considerably from various geographical varieties found in the Far West.