all the manifold genera are only partitioningsC of a single supreme and universal genus; and from this principle its immediate consequence: datur continuum formarum,d.e., all varieties of species bound one another and permit no transition to one another by a leap, but only through every smaller degree of distinction, so that from each one can reach another; in a word, there are no species or subspecies that are proximate (in the concept of reason), but inter vening species are always possible, whose difference from the first and second species is smaller than their difference from each other.