An astonishing number of products on which we depend contain ingredients orginally derived from wild plants and animals. Here are but a few such products. They contribute enormously to international trade as well as to our health and comfort.

Forty percent of prescription drugs contain active ingredients derived from plants. Cortisone, which is used chiefly in the treatment of arthritis and allergies, come from yams. The heart stimulant digitalis originates from the common foxglove. Rosy periwinkle is a source of vincristine and vinblastine, two drugs used to combat leukemia. To date, the National Cancer Institute has identified 3,000 species of plants that show potential as anti-cancer agents; 2,000 of them grow in tropical forests.