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68 at that date, and what strides were made during the next few years. To read what was known of the birds and beasts of the Antarctic and then to read Wilson's Zoological Report of the Discovery Expedition is an education in what one man can still do in an out-of-the-way part of the world to elucidate the problems which await him.

The teeth of a crab-eating seal "are surmounted by perhaps the most complicated arrangement of cusps found in any living mammal." The mouth is so arranged that the teeth of the upper jaw fit into those of the lower, and "the cusps form a perfect sieve a hitherto unparalleled function for the teeth of a mammal." The food of this seal consists mainly of Euphausiae, animals much like shrimps, which it doubtless keeps in its mouth while it expels the water through its teeth, like those whales which sift their food through their baleen plates. "This development of cusps in the teeth of the [crab-eating seal] is probably a more perfect adaptation to this purpose than in any other mammal, and has been produced at the cost of all usefulness in the teeth as grinders. The grit, however, which forms a fairly constant part of the contents of the stomach and intestines, serves, no doubt, to grind up the shells of the crustaceans, and in this way the necessity for grinders is completely obviated."

The sea-leopard has a very formidable set of teeth suitable for his carnivorous diet. The Weddell, living on fish, has a more simple group, but these are liable to become very worn in old age, due to his habit of gnawing out holes in the ice for himself, so graphically displayed on Ponting's cinematograph. When he feels death approaching, the crab-eating seal, never inclined to live in the company of more than a few of his kind, becomes still more solitary. The Weddell seal will travel far up the glaciers of South Victoria Land, and there we have found them lying dead. But the crab-eating seal will wander even farther. He leaves the pack. "Thirty miles from the sea-shore and 3000 feet above sea-level, their carcases were found on