Thus in the whole range of organic evolution no essential stage in Organic life has ever been lost, special forms have perished, but organisms presenting every important stage in evolution continue still to exist with the same vital attributes that the first beings of their kind, so far as we can judge from paleontological evidence, possessed. Thus we now have representatives of the whole scheme of phylogenic evolution from the incipient exposition of the uncentralized plasmic group through all the ranges of unicellular organisms to the highest organic evolvement yet known — man. And while all the classes and orders of living beings still have their representatives, the one continuous unity of all life is still expressed by every organism in its ontological development, passing through the same essential stages as in ages past marked the evolution of its ancestors.