The Burgess Animal Book For Children in "More Of Peter's Long-legged Cousins"

"If anything, he is a little bit heavier. But because his hair lies much smoother than yours, you probably would look a little bit bigger if you were sitting beside him. As with his cousin, the Marsh Rabbit, the hair on his feet is thin. His toes are rather long and he can spread them widely, which is a great help in swimming. He doesn't have to take to the water as his little cousin does, for he is a very good runner.