In very many cases it may be said that actual extermination has not taken place, but that in the course of evolution one species has passed into another; species may have been lost, but the race, or phylum endures, just as in the growth of a tree, the twigs and branches of the sapling disappear, while the tree, as a whole, grows onward and upward.
"Animals of the Past"
Frederic A. Lucas
Luminescence is more widespread in this phylum and more characteristic of the group as a whole than any other.
"The Nature of Animal Light"
E. Newton Harvey
The following five lectures contain the most original matter of any, being devoted to "Phylogeny," or the working out of the details of the process of Evolution in the animal and vegetable kingdoms, so as to prove the line of descent of each group of living beings, and to furnish it with its proper genealogical tree, or "phylum."
"Critiques and Addresses"
Thomas Henry Huxley