The secret of the relation between the spiders and the wasps you can read in many a book. You might even guess at it, but there was no guess work about the observer who first studied out this secret. He did not get his knowledge from books. He patiently watched the mud-dauber going about her house building. He knew that her painstaking labour could have but one meaning. She was building not a home for herself, but for her children. The wasp's children are not little wasps, yet they are none the less young wasps for being footless, colourless, wingless, stingless grubs. They are eggs at first of course, just as all insects are. When the mother wasp has one cell of her apartment house finished she concerns herself immediately with stocking the larder. Knowing the tastes of her yet unborn young, she leaves for a time the mud hole, and visits the haunts of certain spiders. Finding one to her liking, she captures it. Not appreciating the fact that the law forbids the use of preservatives in meats, she injects a drop of some wonder-working fluid into the spider and preserves the creature, not only fresh but alive, though paralyzed. Upon the inert body she places an egg, then seals the cell, well assured in her mind that when the grub hatches it will find the food just as she left it and just enough to nourish the young one to maturity. Before your first season of collecting is past you will find yourself bringing home as specimens many insects which you will see are not fully grown. Little grasshoppers, scarcely bigger than a fly yet possessed of such strength of leg that they can hurl themselves into the air for a distance equal to twenty times their own length. How do you know that they are young grasshoppers and not fully grown ones of some tiny race? Look at one closely and you will see a look of youth about him that is unmistakable. He is fuzzy, his head is too big for him, his legs out of all proportion to the rest of him. Then, too, he has no wings, just little buds where the wings will be some day. By these tokens you will know him for a baby. You can find them in all sizes and can have a series to show the stages of growth. This is one of the first steps in the making of a "Life History Collection," far more valuable to the naturalist than a collection containing only mature insects.