natural classification

A complete genealogy would form what is known as a natural classification.

A natural classification of the Vermæ or worms was his first achievement.

And the natural classification gave the order not only of geological succession but also of stages of embryonic development.

Though he has not laid down any natural classification by genera, he often points out very well the true relations of beings.

He owed  something to Cuvier, yet he knew how to utilize the work in anatomy offered by Cuvier in making a natural classification.