and dasyures over those of Aiistralia; the moas and other wingless birds flourished in the then more extensive land of New Zealand, and the levels under the Rocky Mountains afforded sustenance to herds of mighty animals still, as well as the South African table-lands.
It seems a remarkable fact in the history of organic life, that whilst so many of the contemporary animals have succumbed under various influences during the lapse of time, these great birds of New Zealand should have continued to exist from far earlier ages still until very recent years (if indeed there are not individuals yet remaining), and is probably due to the persistence of an equable climate prevailing over a land in which they had no competitors.
The struggle for life must, as the author of the "History of Creation" admits, have been severe indeed—"fearful," as he remarks—for all forms of tropical fauna and flora especially; hemmed in on a narrow zone between two icy walls stretching nearly from pole to pole, the climate for them must have been rigorous in the extreme. There was in this crowded place of refuge, to which he observes all those wise creatures withdrew "who wished to escape being frozen," an excellent opportunity afforded for the extinction of many nearly effete tribes, and the survival of the fittest; it certainly appears to have been an inconvenient time for man to have begun to push his way—100,000 years ago, Herr Haëckel's date for pliocene men, being the great ice age according to Sir Charles Lyell. Unless development has proceeded since with more rapid strides than this writer assumes with his master it did during previous geological eras, primæval men must have witnessed strange scenes.
The migration of the survivors, leaving in many cases no representatives behind them, is a difficult problem to solve,—the wingless birds to their special island habitats; the rodents of South America to theirs, leaving the monotremes and marsupials in sole possession of their ancestral domains.
Without incurring the risk of being deemed deserving of the contemptuous indignation poured upon those "old stagers grown grey in opposite views" who, with "ridiculous arrogance," object under these difficult circumstances to receive the whole theory of descent as enunciated, and the correct pedigrees as offered by so eminent an authority and adventurous a thinker as the author of this history, we may be permitted to ask for some explanation of the formidable objections that stand in the way of our believing in this narrow zone amidst universal ice. The generality of persons who may read his work will scarcely be satisfied by his assurance that "proofs demanded are needless."
