THE BIOTIC COMMUNITY.

The article explores attitudes of ecologists toward the place of animals in natural communities. Several concepts concerning the relations of plants and animals in natural communities are presented. As biotic factors, animals are external to the plant community, and are considered to have a profound influence on the nature and the economy of vegetation. Another concept states that there are animal communities to which the plants are a part of the habitat. A third concept describes the interrelationship of plants and animals, as they co-act as constituents of an integrated biotic community.