was the last day of Old Mother Nature's school in the Green Forest, and when jolly, round, bright Mr. Sun had climbed high enough in the blue, blue sky to peep down through the trees, he found not one missing of the little people who had been learning so much about themselves, their relatives, neighbors and all the other animals in every part of this great country. You see, not for anything in the world would one of them willingly have missed that last lesson.

"I told you yesterday," began Old Mother Nature, "that the land is surrounded by water, salt water, sometimes called the ocean and sometimes the sea. In this live the largest animals in all the Great World and many others, some of which sometimes come on land, and others which never do.

"One of those which come on land is first cousin to Little Joe Otter and is named the Sea Otter. He lives in the cold waters of the western ocean of the Far North. He much resembles Little Joe Otter, whom you all know, but has finer, handsomer fur. In fact, so handsome is his fur that he has been hunted for it until now. He is among the shyest and rarest of all animals, and has taken to living in the water practically all the time, rarely visiting land. He lies on his back in the water and gets his food from the bottom of the sea. It is chiefly clams and other shellfish. He rests on floating masses of sea plants. He is very playful and delights to toss pieces of seaweed from paw to paw as he lies floating on his back. Of course he is a wonderful swimmer and diver. Otherwise he couldn't live in the sea.

"Another who comes on land, but only for a very short distance from the water, is called the Walrus. He belongs to an order called Finnipedia, which means fin-footed. Instead of having legs and feet for walking, members of this order have limbs designed for swimming; these are more like fins or paddles than anything else and are called flippers. The Walrus is so big that I can give you no idea how big he is, excepting to say that he will weigh two thousand pounds. He is simply a great mass of living flesh covered with a rough, very thick skin without hair. From his upper jaw two immense ivory tusks hang straight down, and with these he digs up shellfish at the bottom of the sea. It is a terrible effort for him to move on shore, and so he is content to stay within a few feet of the water. He also lives in the cold waters of the Far North amidst floating ice. On this he often climbs out to lie for hours. His voice is a deep grunt or bellowing roar. The young are born on land close to the water.

"The Sea Lions belong to this same fin-footed order. The best known of these are the California Sea Lion and the Fur Seal, which is not a true Seal. The California Sea Lion is also called the Barking Sea Lion because of its habit of barking, and is the best known of the family. It is frequently seen on the rocks along the shore and on the islands off the western coast. These Sea Lions are sleek animals, exceedingly graceful in the water. They have long necks and carry their heads high. They are covered with short coarse hair and have small, sharp-pointed ears. Their front flippers have neither hair nor claws, but their hind flippers have webbed toes. They are able to move about on land surprisingly well for animals lacking regular legs and feet, and can climb on and over rocks rapidly. Naturally they are splendid swimmers.

"The largest member of the family is the Steller Sea Lion, who sometimes grows to be almost as big as a Walrus. He is not sleek and graceful like his smaller cousin, but has an enormously thick neck and heavy shoulders. His voice is a roar rather than a bark. The head of an old Sea Lion is so much like that of a true Lion that the name Sea Lion has been given this family.

"The most valuable member of the family, so far as man is concerned, is the Fur Seal, also called Sea Bear. It is very nearly the size and form of the California Sea Lion, but under the coarse outer hair, which is gray in color, is a wonderful soft, fine, brown fur and for this the Fur Seal has been hunted so persistently that there was real danger that soon the very last one would be killed. Now wise and needed laws protect the Fur Seals on their breeding grounds, which are certain islands in the Far North. The young of all members of this family are born on shore, but soon take to the water. The Fur Seal migrates just as the birds do, but always returns to the place of its birth. Man and the Polar Bear are its enemies on land and ice, and the Killer Whale in the water. Mr. Fur Seal always has many wives and this is true of the other members of the Sea Lion family and of the Walrus. The males are three or four times the size of the females. Among themselves the males are fierce fighters.

"The true Seals are short-necked, thick-bodied, and have rather round heads with no visible ears. The Walrus and Sea Lions can turn their hind flippers forward to use as feet on land, but this the true Seals cannot do. Therefore they are more clumsy out of water. Their front flippers are covered with hair.

"The one best known is the Harbor or Leopard Seal. It is found along both coasts, often swimming far up big rivers. It is one of the smallest members of the family. Sometimes it is yellowish-gray spotted with black and sometimes dark brown with light spots.

"The Ringed Seal is about the same size or a little smaller than the Harbor Seal and is found as far north as it can find breathing holes in the ice. You know all these animals breathe air just as land animals do. This Seal looks much like the Harbor Seal, but is a little more slender.

"Another member of the family is the Harp, Saddle-back or Greenland Seal. He is larger than the other two and has a black head and gray body with a large black ring on the back. The female is not so handsome, being merely spotted.

"The handsomest Seal is the Ribbon Seal. He is about the size of his cousin the Harbor Seal. He is also called the Harlequin Seal. Sometimes his coat is blackish-brown and sometimes yellowish-gray, but always he has a band of like a broad ribbon, from his throat around over the top of his head, and another band which starts on his chest and goes over his shoulder, curves down and finally goes around his body not far above the hind flippers. Only the male is so marked. This Seal is rather rare. Like most of the others it lives in the cold waters of the Far North.

"The largest of the Seals is the Elephant Seal, once numerous, but killed by man until now there are few members of this branch of the family. He is a tremendous fellow and has a movable nose which hangs several inches below his mouth.

"The queerest-looking member of the family is the Hooded Seal. Mr. Seal of this branch of the family is rather large, and on top of his nose he carries a large bag of skin which he can fill with air until he looks as if he were wearing a queer hood or bonnet.

"The Seals complete the list of animals which live mostly in the water but come out on land or ice at times. Now I will tell you of a true mammal, warm-blooded, just as you are, and air-breathing, but which never comes on land. This is the Manatee or Sea Cow. It lives in the warm waters of the Sunny South, coming up from the sea in the big rivers. It is a very large animal, sometimes growing as big as a medium-sized Walrus. The head is round, somewhat like that of a Seal. The lips are thick and big, the upper one split in the middle. The eyes are small. It has but two flippers, and these are set in at the shoulders. Instead of hind flippers, such as the Seals and Sea Lions have, the Manatee has a broad, flattened and rounded tail which is used as a propeller, just as fish use their tails. The neck is short and large. In the water the Manatee looks black. The skin is almost hairless.

"This curious animal lives on water plants. Sometimes it will come close to a river bank and with head and shoulders out of water feed on the grasses which hang down from the bank. The babies are, of course, born in the water, as the Manatee never comes on shore. Now I think this will end to-day's lesson and the school."

Peter Rabbit hopped up excitedly. "You said that the largest animals in the world live in the sea, and you haven't told us what they are," he cried.

"True enough, Peter," replied Old Mother Nature pleasantly. "The largest living animal is a Whale, a true mammal and not a fish at all, as some people appear to think. There are several kinds of Whales, some of them comparatively small and some the largest animals in the world, so large that I cannot give you any idea of how big they are. Beside one of these, the biggest Walrus would look like a baby. But the Whales do not belong just to this country, so I think we will not include them.

"Now we will close school. I hope you have enjoyed learning as much as I have enjoyed teaching, and I hope that what you have learned will be of use to you as long as you live. The more knowledge you possess the better fitted for your part in the work of the Great World you will be. Don't forget that, and never miss a chance to learn."

And so ended Old Mother Nature's school in the Green Forest. One by one her little pupils thanked her for all she had taught them, and then started for home. Peter Rabbit was the last.

"I know ever and ever so much more than I did when I first came to you, but I guess that after all I know very little of all there is to know," said he shyly, which shows that Peter really had learned a great deal. Then he started for the dear Old Briar-patch, lipperty-lipperty-lip.