Many, many years ago when the world was new, the Mississippi river was much longer than it is now. It meandered back and forth across the area that is now Minnesota. Fish in great numbers lived in this river, and its water was so pure and sweet that all the animals came there to drink.

A giant moose that lived way up north heard about the river and he too came there to drink. But he was so big, and he drank so much, that soon the water began to sink lower and lower. The beavers were worried. The water around their lodges was disappearing. Soon their homes would be destroyed. The muskrats were worried, too. What would they do if the water vanished? How could they live? The fish were very worried. The other animals could live on land if the water dried up, but they couldn't. All the animals tried to think of a way to drive the moose from the river, but he was so big that they were too afraid to try. Even the bear was afraid of him.

At last the Fly said he would try to drive the moose away. All the animals laughed and jeered. How could a tiny fly frighten a giant moose? The fly said nothing, but that day, as soon as the moose appeared, he went into action. He landed on the moose's foreleg and bit sharply. The moose stamped his foot to shake off the fly. But, the fly landed again and bit again and the moose stomped harder, and each time he stamped, the ground sank and the water rushed in to fill it up.

Then the fly jumped about all over the moose, biting and biting and biting until the moose was in a frenzy. He dashed madly about the banks of the river, shaking his head, stamping his feet, snorting and blowing, but he couldn't get rid of that pesky fly. Finally, the moose could take it no longer and ran far away back up to the far north country where he had come from.

All the thrashing and stomping that the giant moose did across the country created large and small holes. As these filled with water, they became the 10,000 lakes of Minnesota. And, the giant moose told all the other moose to never go south because of the terrible biting flies there. That is why there are no longer moose in Minnesota except way up north by Canada.

The fly was very proud of his achievement, and the other animals were very thankful. They made a promise to Fly that whenever any animal dies of old age or disease, the fly can have the entire body to feed on and lay eggs. That is how it is done to this day.