Pagoo, by Holling C. Holling

A detailed study of tide pool life is presented in text and pictures through the story of Pagoo, a hermit crab. A perfect story for fourth grade "Human and Animal" classes, or nature studies.The story begins...Little Pagurus- "Pagoo" for short- floated at the surface of the sea. Pagurus (Pa-gu-rus) would grow into a two-fisted Hermit Crab- if he could make it. Someday he would live near shore, walking on a sea floor of rock and sand. But before he could walk on the sea's bottom he must drift on its top, as helpless as atiny fleck of foam...