Animals of a great many different kinds have helped show man the way, in taking advantage of the opportunities which nature affords him to feed, clothe and protect himself, but one of the smallest of the animal kingdom is probably the cleverest of all--the spider. Spiders have many different kinds of enemies, ranging from man down to the very smallest, but dangerous, insects, and most of their enemies possess enormous advantages over them in either strength or agility, or both combined; enemies with wings, swift in movement and able to retreat where the spider cannot follow them; enemies clad in an impenetrable coat of armor, against which the spider’s weapons are powerless, while the spider’s own body is soft and vulnerable. These handicaps have been met by the spider with a multitude of clever contrivances, and if invention and skill are to be regarded as an index to intellectual development, it should be very significant to realize how far spiders are ahead of our near relatives, the almost human members of the monkey family. One of the most interesting of the spider race is the “trap-door” spider which inhabits warm countries all over the earth. The “trap-door” spider not only builds a home for herself by digging a deep hole in the ground and lining it with silk to prevent the sides from falling in, but she also adds a neat little door to keep out the rain and other troublesome things. She usually chooses sloping ground for her homestead so that the door, which she fastens at the edge of its highest point by a strong silk-elastic hinge, swings shut of its own weight after being opened. She disguises the entrance to her home in a manner superior to the famous art of concealment practiced by the Indians, by planting moss on the outside of the door--living moss taken from the immediate neighborhood--so that the entrance to her house harmonizes perfectly with its surroundings, its discovery being made more difficult by the fact that in her careful selection of a site for her dwelling she also appears to be influenced by the presence of patches of white lichen which distract the eye. The male spider does not seem to take any part in designing, constructing or decorating the home and does not even share its occupancy, leaving it to the mother and her family--often forty or more children at a time--and living a vagrant life, camping out in holes and ditches when he is not tramping around over the whole countryside. The mother spider, however, like many other animals, takes excellent charge of her children, and guards them carefully from all harm. At the first sign of a commotion going on outside her front door she is known to invariably assemble her family behind her, out of harm’s way, and then place her back against the swinging door, holding it shut with some of her feet and clinging tightly to the inner walls of her home with the others.