Of animals' houses
Two sorts are found -
Those which are square ones
And those which are round.

Square is a hen-house,
A kennel, a sty:
Cows have square houses
And so have I.

A snail's shell is curly,
A bird's nest round;
Rabbits have twisty burrows
Underground.

But the fish in the bowl
And the fish at sea -
Their houses are round
As a house can be.

James Reeves

George Redgrave

http://www.poemhunter.com/poem/animals-houses/