Crocodiles and other tropical animals take very long naps during the hottest weather. Hartwig's "Harmonies of Nature" tells about an officer who was asleep in a tent in the tropics, when his bed moved under him, and he found it was because a crocodile, in the earth beneath, was just waking up! Imagine what the dried-up ponds and streams of the llanos of South America must look like when the rainy season comes on, after the dry spell, with crocodiles asleep just under the surface everywhere. Doctor Hartwig's book tells. But the most remarkable case of drying up that ever I heard of was that of the Egyptian snail in the British Museum, that Woodward tells about in his "Manual of the Mollusca." This snail was sent to England, simply as a shell, in 1846. Never dreaming there was anybody at home, they glued him to a piece of cardboard, marked it _Helix Desertorum_, and there he stuck until March 7, 1850, when somebody discovered a certain thing that indicated that there _was_ somebody "at home," and that he was alive. They gave him a warm bath and he opened his four eyes on the world! In his "Animal and Vegetable Hedgehogs" ("Nature's Work Shop") Grant Allen tells why the hedgehog works at night and sleeps in the daytime. How he fastens on his winter overcoat of leaves, using his spines for pins, and how funny it makes him look. How Mother Nature manages to have breakfast ready for him in the Spring just when he is ready for _it_. How hedgehogs use their spines when they want to get down from a high bank or precipice real quickly. How their eyes tell how smart they are; for a hedgehog is smart. You will also find interesting things about hibernation in Gould's "Mother Nature's Children" and Richard's "Four Feet, Two Feet and No Feet." In one of his essays on nature topics--"Seven Year Sleepers"--Grant Allen tells how the toad goes to bed in an earthenware pot, which he makes for himself, and how this habit may have helped start the story that live toads are found inside of stones. Ingersoll, in that delightful book I have already referred to several times, "The Wit of the Wild," calls the pikas "the haymakers of the snow peaks." In his article on these interesting little creatures, he tells why you may often be looking right at one and still not see it; why the pikas gather bouquets and why they always lay them out in the hot sun; why their harvest season only lasts about two weeks, and why, although they usually go to bed at sunset, they work far into the night in harvest time.