If they are lucky, the stooping figures busily combing a Florida beach (above) will rub away the sand from a hard calcium object and find underneath a shell which, like the beauties pictured opposite, will compare favorably with the fanciest jewels yet devised by man or nature. Almost any child or adult who has ever roamed a beach has probably enjoyed the thrill of discovering one such shell, but to the systematic collector it is an experience that has become almost commonplace. For collectors, a cheerful and obsessed band of hobbyists who sometimes go to amazing lengths to get hold of a particular shell, operate in an enormous and still largely unexplored world, in which the very names attest poetically to the infinite variety of its color and form: lion's-paw, angel wing, Venus's-comb, bleeding tooth, jewel box, baby's-cradle, silver lantern, Scotch bonnet, precious tusk and sad unicorn.
Shells are the liquid cement secretion of animals called mollusks which wear their skeletons on the outside. There are 80,000 known species; about 500 new ones are being found every year, and there may be another 50,000 awaiting discovery. Mollusks can be found in the ocean, on mountains, near the poles, on the desert, on the tops of trees and under their roots, in the jungle, in fresh-water ponds and even in hot springs. They climb, crawl, burrow, swim, dive, float, spin a web, and some fly. Certain species are bisexual. Others change sex with confusing frequency; and one, the California sea hare, is so prolific it is said to spawn around 100 million eggs a month. Some eat voraciously, others hibernate for years without nourishment. A few are venomous and can kill a man. Many are microscopic, but the giant clam of the Pacific's coral reefs often reaches a thumping 500 pounds.
Regardless of their size, however, most mollusks maintain an absolute mathematical control over their own growth, so that their perfect symmetry is never marred. (Each new coil of the celebrated chambered nautilus, for example, is built exactly three times the width of the coil preceding it.) The patterns and colors ornamenting the shells are produced by a series of pigment glands on the edge of a flap of skin called the mantle. Unfortunately, of the untold billions of shells washed up on the world's shores each year, only one percent are worth saving, the abrasive action of wind, sand and sea having dimmed their color and softened their form.
Probably the most sought-after shell in the world is the gold-and-porcelain glory-of-the-sea cone (page 34), three of which were first sighted in the Philippines in 1838. Only 23 can be located today, making them extremely valuable, but the bottom could fall out of the market in a flash if a collector should stumble on a large colony, as happened a few years ago with the golden-mouthed Busy con. Only two were known to exist. Then one day some Florida shrimp men came in with 100 specimens. Dealers immediately downpriced the shell to $5 for their good customers, and then learned to their horror that the action was hasty. The shrimpers have never dredged up another golden-mouth.
Shells are at their best and most prolific in warm waters. In the U.S. and environs the outstanding spots are the lazy beaches of Magdalena Bay on the southwest coast of Baja California and the palm-lined sands of Sanibel Island, off Fort Myers on the Gulf Coast side of Florida. The intensive collector gets shells any way he can—buying, trading, fishing, trawling, digging, diving, etc.—but if he is an old hand at the game, he will let a hermit crab do the work for him. This little creature lives in a shell to protect an extremely tender section of his anatomy. If the collector takes away his shell, this important-looking crab will march into the sea, pick up a new one and lug it ashore. With luck, it will be a good one.