_Spring Azure_ (_Cyaniris ladon_ or _Lycaena ladon_). Wing expanse 1 inch. No tails on hind wings. Eyes hairy. Upper wing surface azure blue with black border markings varying greatly, more pronounced in the female. Lower wing surface slaty brown with many darker spots. PART III THE SKIPPER BUTTERFLIES SUPERFAMILY _Hesperioidea_ The true butterflies are so distinct in their structure and many of their habits from the Skippers that the most careful students of the order are pretty well agreed in making the two great superfamilies--Papilionoidea, the true butterflies, and Hesperioidea, the Skipper butterflies. The latter includes these two families: The Giant Skippers (_Megathymidae_). The Common Skippers (_Hesperiidae_). These insects as a whole are distinguished from the higher butterflies by their large moth-like bodies, small wings, hooked antennae (except in the Giant Skippers), by having five branches of the radius vein arising from the large central cell. The larvae spin slight cocoons in which to pupate and the pupae are rounded rather than angular. The two families are readily distinguished by the differences in their size and the structure of the antennae. The Giant Skippers measure two inches or more across the expanded wings and have comparatively small heads, with the clubs of the antennae not pointed or recurved. The Common Skippers are smaller, and have very large heads with the antennal clubs drawn out and recurved. THE GIANT SKIPPERS FAMILY _Megathymidae_ Although large in size, the Giant Skippers are few in numbers. Only one genus and five species are listed for North America, and practically all of these are confined to the Southwestern states and Mexico. Some of them extend as far north as Colorado and as far east as Florida. [Illustration: Megathymus yuccae. Female. (After Riley.)] So far as the story of its life is concerned, the best-known species is the Yucca-borer Skipper (_Megathymus yuccae_) which was carefully studied by the late Dr. C. V. Riley. As will be seen from the picture above which represents the adult, natural size, this skipper has a body so large as to suggest some of the heavy-bodied moths. The wings are dark brown, marked with red-brown spots and bands. They fly by day and when at rest hold the wings erect. These adults lay eggs upon the leaves of Spanish needle or yucca. The eggs soon hatch into little caterpillars which at first roll parts of the leaves into cylinders, fastening the sides in place by silken threads, and later burrow into the stem and root, often making a tunnel a foot or more deep. Here the caterpillars remain until full grown. They are then nearly four inches long and half an inch in diameter. They now pupate in the top of their tunnel and in due season emerge as adults. THE COMMON SKIPPERS FAMILY _Hesperiidae_