Part 2

X. THE WORMS 73

XI. THE TWO-VALVED SHELLS 89

XII. THE UNIVALVES 103

XIII. THE CUTTLEFISHES 117

XIV. THE CRUSTACEANS 128

XV. FROM BARNACLES TO LOBSTERS 134

XVI. THE CRABS 145

XVII. LUMINOUS CRABS 156

XVIII. THE INSECTS 159

XIX. LOWER FORMS OF INSECTS 164

XX. THE SPIDERS 168

XXI. SOME SIX-LEGGED INSECTS 178

XXII. SOME MIMICS 186

XXIII. THE GRASSHOPPERS AND LOCUSTS 190

XXIV. THE BEETLES 195

XXV. THE BUGS 199

XXVI. FLIES AND MOSQUITOES 204

XXVII. THE BUTTERFLIES AND MOTHS 212

XXVIII. THE ANTS 222

XXIX. THE BEES AND WASPS 228

INDEX 233

HALF HOURS WITH

THE LOWER ANIMALS

PROTOZOANS, SPONGES, CORALS, SHELLS, INSECTS, AND CRUSTACEANS

I. INHABITANTS OF A DROP OF WATER

The most unobserving stroller through the forest or by the seashore can not fail to be impressed by the abundance and variety of animal life; yet the forms visible to the naked eye really constitute but a fraction of the vast horde which makes up what we call life.

In the year 1901 a strange phenomenon appeared off the coast of southern California. The ocean assumed a reddish muddy hue which was traced for four hundred miles up the coast and from one to twenty miles offshore; hence, at a conservative estimate, the reddish color occupied a space of ten thousand square miles. At night it assumed a greenish light, and when the wind rose and formed whitecaps, each became a blaze of light, and the ocean as far as the eye could reach was converted into a mass of seeming flame. The sands of the beach gave out flashes of light when touched; the footsteps of dog or man on the sands left an imprint of vivid light, and figures made on the sands with a finger or stick stood out in lines of light. Ten thousand square miles of phosphorescent light; ten thousand square miles of living beings, each so minute that it was almost if not quite invisible to the human eye. Who could estimate the individuals in one square mile, one square foot, or even a drop of this reddish water? This illustrates the fact that the greater number of the earth's population are unseen, even though not invisible to the unaided eye.

These minute animals are as interesting as the larger forms. Equipped with a microscope, we are prepared to explore the regions in which they live and observe their habits. A favorite hunting ground for this small game is some long-standing water in which plants have been growing. Placing some of this, with the green scraping of the glass, on the slide, we shall soon make out, moving mysteriously along, something which resembles the white of an egg, an atom of slime or jelly. Now it stops and throws out parts of itself which seem to fuse together again; now it is long, now short and compact, again circular. You almost believe it is a mere atom of slime, yet it is an animal which eats and lives its life cycle in a drop of water, one of the lowest of all animals.