Joe Davis, age 9, of Des Moines, Iowa, for his question::

How big; is the biggest living animal?

The gentle giraffe is the tallest animal in the world and the elephant is the biggest animal you will ever find in the zoo. Jumbo may weigh four tons. He needs about 150 pounds of hay every day and he is smart enough to learn the meaning of about 25 different words. But the tall giraffe and the bulky elephant are both little fellas compared with the biggest living animal.

We find the biggest living animal in the. sea, for he roams in the deep oceans usually far from the shores. You could walk around inside his huge mouth and standing beside him, an elephant would look no bigger than a poodle dog. Mr. Big is also a smart animal. We have not had much  chance to train this deep water giant, but some experts think that he is one of the most intelligent animals in the world.

Mr. Big is the giant of the giant whale family of animals. We may call him the blue whale, the blue baleen whale or the sulphur bottom whale. From head to tail he may measure 100 feet. This is hard to imagine unless we use something with which to compare him. You can, of course, measure off 33 yards of distance on the ground. This will show you the length of the giant. It is more fun to measure him with imaginary elephants.

Take one big jumbo standing on the ground. Stand another elephant on his head, then another elephant and another until you have ten elephants standing on each other's heads. Now take one blue whale from the ocean and Pave him stand upright on the tip of his tail. He will be just about as tall as the column of ten elephants.

The big whale, however, weighs more than 25 elephants. The biggest living animal weighs more than 100 tons. He needs about a ton of food a day.    

You might guess that the powerful giant catches codfish and herring, sharks, mackerel and all kinds of sizeable fish. But this is not so, for his tiny throat can swallow nothing bigger than a shrimp. He feeds on plankton. This is a soupy mixture of small seaweeds, fish eggs and a wide assortment of small plants and animals floating in the sea.

The big fellow is called a baleen whale because he has baleen instead of teeth. Baleen or whalebone is somewhat like tough, bendable plastic. The blue whale has about 300 strips of baleen hanging from the roof of his mouth and some of them may be 10 feet long. When he gulps a mouthful of water, the baleen fringe acts as a strainer to sift out the plankton. The whale swallows the wad of soft food down his small throat and sends the water back into the ocean.