Can you imagine an insect daring enough to brave the stings of the thousands of workers in a bee's nest? This wingless, solitary female ant lives habitually in their nests and eats the food they have so busily gathered, an unbidden and probably a most unwelcome guest. Powerful jaws, formidable sting, an armor-plated shell to protect her from the stings of the bees and wasps in whose nests she lives, seem to fit her for the strange life she leads. If you should find her mate he would doubtless be on the wing, for unlike all others of the order, it is the male alone which flies. So different from their mates do some of these male cow killers look that they have often been mistaken for quite different species. It is supposed that the female lays her eggs inside a bumble-bee grub and in a few days' time they hatch and eat the babies up, from the inside outwards. Then they hatch again, so to speak, as full-fledged cow killers and feast upon the honey of their hosts. [Illustration] THE WORKER BUMBLE-BEE (_Bombus vagans_, Sm.) Everybody has a friendly feeling for the bumble-bee, that clumsy rover of the clover field whose buzzing seems part of the still summer air. She is the real worker of the hive, an undeveloped female, her hind legs laden with a mass of pollen from the flowers she has visited, and her honey sac filled with nectar. As every boy who has hunted her nest will know, the bumble-bee lives in burrows under ground. The cells that she makes are of wax, secreted from special plates which lie arranged in rows beneath her hairy body. Each cell is like a little jar, standing on end, quite different from the cells in a honey bee's comb. In some of these the eggs are laid and the baby bees hatch out, while others are filled up with nectar. While the bee is gathering pollen with her legs, she is also gathering nectar with her tongue and storing it in a special honey stomach from which she later regurgitates it into the honey cells in her nest. The nectar, when it is gathered, is thin, like the sap of the maple tree, and, like it, must be condensed. Part of the water seems to be taken out in the honey stomach, and part evaporates from the honey cell. It will, perhaps, be a satisfaction to those who hate getting up early to know that there is a well-founded rumor that some bumble-bees have a trumpeter who, somewhere between three and four o'clock in the morning, wakes up the sleepy hive. [Illustration] THE POLLEN PLATES OF THE BUMBLE-BEE (_Bombus americanorum_, Fab.)