It is believed that most of the world's walnut varieties derive from the original species still found here.

The original species can mostly be found in temperate areas on Earth.

More important, they found that none of the original species in either river had become extinct.

This place is so fascinating, so full of original species.

A blight killed the American chestnut, another original species, at the turn of the century.

That's not bad, but it does mean that the original species diminish.

There are many such mixed species, and few original species.

Some are nurtured into workers themselves, who gradually replace the original species in the nest.

It is treason I contemplate, by the definition of my original species.

The original species had only about 15 flowers on rather floppy stems.