THE PATH OF VISION
causes, which in brief periods produce varieties, in long periods give rise to types; how the colors of animals are useful for concealment from their prey; how they are acquired, transmitted, distributed, and lost. He also discoursed of the hoof of the horse, and how it developed from a thickened nail; of the pest insects and scales threatening the ruin of orchards, and how they can be fought by insect allies; of the grasshoppers, and how they may be killed by a fungus disease cultivated for that purpose; of the colors and scents of blossoms, and how they attract insects and bees; of plants that hold the key to buried wealth, indicating as they do mineral veins. These, and many more fascinating and useful details, Science can relate. But the fact that they are useful soon dispels the fascination. And my learned friend the naturalist was silent when I asked him to explain to me the life-principle of growth and decay in the butterwort, the black scale, the woodchuck, or the lion. I did not mention man, whose romance, as
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