solitary; or in other
ways besides,--and any one of these ways may suit him to many widely
different environments.

Readers of Mr. A. R. Wallace will well remember the striking
illustrations of this in his Malay Archipelago:--

"Borneo closely resembles New Guinea not only in its vast size and its
freedom from volcanoes, but in its variety of geological structure, its
uniformity of climate, and the general aspect of the forest vegetation
that clothes its surface; the Moluccas are the counterpart of the
Philippines {240} in their volcanic structure, their extreme fertility,
their luxuriant forests, and their frequent earthquakes; and Bali, with
the east end of Java, has a climate almost as dry and a soil almost as
arid as that of Timor. Yet between these corresponding groups of
islands, constructed, as it were, after the same pattern, subjected to
the same climate, and bathed by the same oceans, there exists the
greatest possible contrast when we compare their animal productions.
Nowhere does the ancient doctrine that differences or similarities in
the various forms of life that inhabit different countries are due to
corresponding physical differences or similarities in the countries
themselves, meet with so direct and palpable a contradiction. Borneo
and New Guinea, as alike physically as two distinct countries can be,
are zoologically wide as the poles asunder; while Australia, with its
dry winds, its open plains, its stony deserts, and its temperate
climate, yet produces birds and quadrupeds which are closely related to
those inhabiting the hot, damp, luxuriant forests which everywhere
clothe the plains and mountains of New Guinea."

Here we have similar physical-geography environments harmonizing with
widely differing animal lives, and similar animal lives harmonizing
with widely differing geographical environments. A singularly
accomplished writer, E. Gryzanowski, in the North American Review,[11]
uses the instances of Sardinia and Corsica in support of this thesis
with great effect He says:--

"These sister islands, lying in the very centre of the Mediterranean,
at almost equal distances from the centres of Latin and Neo-Latin
civilization, within easy reach of the Phoenician, the Greek, and the
Saracen, with a {241} coast-line of more than a thousand miles, endowed
with obvious and tempting advantages, and hiding untold sources of
agricultural and mineral wealth, have nevertheless remained unknown,
unh