Randy Reynolds, age 12, of Victoria, for his question:

Is the platypus a bird or a mammal?

In 1799 experts in London received a package from Australia, containing the stuffed body of a furry little animal with webbed feet and a sort of duck bill. This, decided the experts, is a clever fake of the taxidermists' art. They refused to believe such an animal existed. The duckbill platypus seems to be put together from spare parts and is enough to baffle any expert.

 He has webbed feet like a goose and a rich fur coat like an otter. Mr. Platypus has snaky poison glands in the claws of his back feet. Mrs. Platypus lays eggs and, when the babies hatch, feeds them on mother's milk. What’s more, every platypus has a sort of duck bill. However, among all these confusing details, one fact places the platypus in the class of mammals. All mammal babies and only mammal babies are fed on mother is milk.

Australia is a land of strange animals. It is the home of the marsupials, or pouched animals. These creatures once existed all over the world. In most places they became extinct as the fanged, meat‑eating animals developed. Geologists believe that Australia and its islands were once closer to the vast land masses of Asia, Africa and Europe. They seam to have separated and drifted away, taking with them their plants and animals.

This, we are told, most likely happened before the meat-eating animals developed. And too, they never did develop in Australia. The marsupids were safe. And so was the platypus. These animals are direct descendants of ancient forms of life which once existed over most of the world. The platypus especially has bean called a living fossil.

The experts regard the platypus as a sort of missing link. But he definitely does not link the mammals to the bird world. In many respects he links the mammals to the reptiles. The small white eggs are soft shelled, like reptile eggs. The poison in papas spurs resembles snake venom. We are told that the first mammals had reptile ancestors. The platypus is a mammal who retains certain features of his reptile ancestors.

The strange fellow is rarely seen, even at home in Tasmania and eastern Australia, He is a shy creature who prefers to hunt at night. His home is a burrow in a muddy river bank. Inside it is a nest lined with dry grass. He loves the orator and swims like an otter. Two little nostrils near the end of his nose allow him to breathe when almost entirely under orator.

The famous bill is shaped like a duck's. However, a ducks bill is made of hard, horny material. The bill of the platypus is mare like leather or rubber. He uses it to dig in the mud for grubs and snails. The duckbill platypus belongs in the order Monatremata, the lowest order of the noble class Mammalia.