As for Old Mother Nature, she smiled indulgently. “Put on your thinking-caps, you two,” said she. “You haven't named half of them. You are not wholly to blame for that, for some of them you never have seen, but there is one member of the Squirrel family whom both of you know very well, yet whom neither of you named. Put on your thinking-caps.”
Chatterer looked at Happy Jack, and Happy Jack looked at Chatterer, and each scratched his head. Each wanted to be the first to think of that other cousin, for each was jealous of the other. But though they scratched and scratched their heads, they couldn't think who that other cousin could be. Old Mother Nature waited a few minutes before she told them. Then, seeing that either they couldn't remember or didn't know, she said, “You didn't mention Johnny Chuck.”
“Johnny Chuck!” exclaimed Chatterer and Happy Jack together, and the look of surprise on their faces was funny to see. For that matter, the looks on the faces of Peter Rabbit and Jumper the Hare were equally funny.
Old Mother Nature nodded. “Johnny Chuck,” she repeated. “He is a member of the Squirrel family. He belongs to the Marmot branch, but he is a Squirrel just the same. He is one of your cousins.”
“He's a mighty funny looking Squirrel,” said Chatterer, jerking his tail as only he can.
“That just shows your ignorance, Chatterer,” replied Old Mother Nature rather sharply. “I'm surprised at the ignorance of you two.” She looked first at Chatterer, than at Happy Jack. “It is high time you came to school to me for a while. You've got a lot to learn. For that matter, so have Peter and Jumper. Now which of you can tell me what order you all belong to?”
Happy Jack looked at Chatterer, Chatterer looked at Peter Rabbit, and Peter looked at Jumper the Hare. On the face of each was such a funny, puzzled expression that Old Mother Nature almost laughed right out. Finally Peter Rabbit found his tongue. “If you please,” said he, “I guess we don't know what you mean by an order.”
“I thought as much,” said Old Mother Nature. “I thought as much. In the first place, the animals of the Great World are divided into big groups or divisions, and then these groups are divided into smaller groups, and these in turn into still smaller groups. Happy Jack and Chatterer belong to a group called the Squirrel family, and Peter and Jumper to a group called the Hare family. Both of these families and several other families belong to a bigger group called an order, and this order is the order of Gnawers, or Rodents.”
Peter Rabbit fairly jumped up in the air, he was so excited. “Then Jumper and I must be related to Happy Jack and Chatterer,” he cried.
“In a way you are,” replied Old Mother Nature. “It isn't a very close relationship, still you are related. All of you are Rodents. So are all the members of the Rat and Mouse family, the Beaver family, the Porcupine family, the Pocket Gopher family, the Pika family, and the Sewellel family.”