Again, the genera Citheronia and Eacles are a South American element in our fauna, while the typical Attacinæ, such as Actias, probably belong to the Old World element in our fauna, together with all our Platypteryginœ. Among the Hawk Moths the genera Philampelus and Phlegethontius are of probable South American extraction, though represented now by certain strictly North American species. Mr. Robert Bunker, writing from Rochester, N. Y., records the fact that Philampelus Pandorus, going into chrysaiis Augnst 1, came out Sept. 10 as a moth, showing that in a warmer climate the species would become doublebrooded. And this is undoubtedly the case with many species the farther we go South, where insect activities are not interrupted so long and so strictly by the cold of winter. Since the continuance of the pupal condition is influenced by cold, a diminishing seasonal temperature for ages may have originally affected, if not induced, the transformations of insects as a whole. Butterflies and Moths which are single brooded in the North become double brooded in the South.