More than 500 species of trees, shrubs, wildflowers, grasses, ferns, mosses and lichens are illustrated and described.

    He was prolific, authoring or editing over eighty books & numerous journal papers which have spawned a huge, fertile continuation of his research over the decades. A major component of any course on children's psychological development & a research tradition that is expanding, scholars need access to the original texts rather than relying on secondhand accounts. "Jean Piaget: Selected Works" is a chance to acquire key original texts, most of which have been previously unavailable for years.