No doubt organic beings, like all other objects, can be classed in many ways, either artificially by single characters, or more naturally by a number of characters.

We know, for instance, that minerals and the elemental substances can be thus arranged.

In this case there is of course no relation to genealogical succession, and no cause can at present be assigned for their falling into groups.

But with organic beings the case is different, and the view above given accords with their natural arrangement in group under group; and no other explanation has ever been attempted.