Gyr-inus natator. We have all seen them looking so trim and tight iii their steel-blue armor, whirling about each other by means of invisible legs, or huddling together side by side in the sociable fashion. If we manage to catch one he will prove worth looking at, as much so as an elephant, when one gets his eyes open and full of curiosity to learn of everything. With a little pocket glass we may plainly see that there are two prominent beetle eyes on each side of the head. These are joined side by side, and when the beetle is on the water the lower eye is under the surface and the upper one out of water. This is a very convenient arrangement for a creature with fish enemies be-
' neath him and bird enemies above him. Now this beetle belongs to a group of insects that are good crawlers, as a rule, but if we capture one of those " whirligigs, " and let him try to walk, we will see that he cannot " get a move on him, " as the boys say. His limbs have become oars and paddles and graspers.
I say they have become thus, because there is abundant evidence to show that they are descendants of beetles that lived on the land, and crawled and flew, as most of them do now. In the always hard struggle for existence the distant forefathers of the " whirligigs " came to frequent banks of streams and ponds, as good