Two canine animals, in a time of dearth, may be truly said to struggle with each other which shall get food and live.

But a plant on the edge of a desert is said to struggle for life against the drought, though more properly it should be said to be dependent on the moisture.

A plant which annually produces a thousand seeds, of which only one of an average comes to maturity, may be more truly said to struggle with the plants of the same and other kinds which already clothe the ground.

The mistletoe is dependent on the apple and a few other trees, but can only in a far-fetched sense be said to struggle with these trees, for, if too many of these parasites grow on the same tree, it languishes and dies.

But several seedling mistletoes, growing close together on the same branch, may more truly be said to struggle with each other.