This class, also know as Eudictos are flowering plants that have two seed leaves upon germination. The term eudicotyledon is from the Greek words eu meaning new, di meaning two and cotyledon from the Ancient Greek word kotulēdōn meaning cup shaped cavity and/or seed leaf. Thus the word eudicotyledon means true two-seed-leaf plant and this word was created to separate true dicots from the older, more primitive flowering plants that were previously called dicots, such as the magnoliids. However, modern genetic testing shows that magnoliids belong to a much older and distinct lineage separate from the eudicotyledons.

The Ericaceae is a large family of flowering plants, containing 126 genera with about 4,250 species commonly known as the heath or heather family which can be either evergreen or deciduous. These flowering plants are found primarily in acidic and/or infertile growing conditions.

There are many well known species in this family which are economically important including the cranberry, blueberry, huckleberry, azaleas, rhododendron, and other various common heaths and heathers.

There is a diverse range of plants within this family which include: herbs, dwarf shrubs, shrubs and trees, most of which normally have evergreen leaves.

The distribution of this family is nearly worldwide due to their being absent from Antarctica, the extreme northern Arctic area and a few other areas.

Tropical and subtropical America

Japan, Kamchatka and Kuril islands

Europe and Asia Minor

Southeastern United States

Portugal

Eastern Atlantic, Europe

Japan and North America

widespread

Japan, Turkey, Eastern North America

South Africa, Madagascar, Mediterranean, Europe

North America, Cuba

Laurel

Oregon, USA

South America

North America and Eurasia

Heath

Asia, North America, Europe, Austraila

Alps and Asia Minor

Non-photosynthetic species

blueberry, bilberry, cranberry, lingonberry, and huckleberry.