H 
VOKKSIIIHK NATL'HALISTS UNION. 
selected siicli inclement places for their abode ; the Polar Bear, that 
incarnation of life in icy regions, has no love of cold, but, on the 
contrary, revels in sunshine and warmth. 
Aictic and Alpine life consists of the more primitive urganisms 
originally behtngin;-- to, and grachially acquired from, the general fauna 
and flora of the more temperate adjacent regions and which are 
achled to from time to time by the acklition of other refugees from 
the unending and relentless struggle for existence for the more 
favoral)le i)ositions that is constantly in operation. 
Mr. Ball has shown the great probability of Alpine plants being 
derived from species inhabiting the surrounding plains, and cf)n- 
v'ersely, therefore, the impiobability of Al])ine species diffusing 
themselves over the neighbouiing less inclement country as lias 
been so often and so erroneously declared ; and this is ecpially tiue 
of the Arctic races and of all life, and as Darwin has so poetically 
expressed it : "as the tide leaves its drift in horizontal lines, rising 
higher on tlie shores where the tide rises highest, so have the living 
waters left their living diift on our mountain summits, in a line 
rising from the Arctic lowlands to a great altitude under the 
Ecluator. The various species thus stranded may be compared with 
the savage races of men driven up and surviving in the mountain 
fastnesses of almost every land, which serve as a record, full of 
interest to us, of the former inhabitants of the surrounding lowlands." 
(geographical distribution when properly understood not only 
discloses the results of illimitable ages of evolution and of endless 
and innumerable conflicts between the numberless species which now 
exist or have existed, and resulting in the extinction or migration of 
the weaker species and genera and the present arrangement of the 
life-groups of the world as the outcome of the whole past history of 
the earth, but reveals, in connection with dominance, the probable 
phylogenetic lineof descent of the various species and grou})S, indicates 
the direction of the migratory movements, and points to the seat or 
area of prei)onderating evolutionary power and is, therefore, a very 
important feature in the study of Nature, being, as the immortal 
Darwin has declared, "a keystone of the laws of creation." 
Some scientists, agreeing with the late Prof. Forbes, apparently 
regard the assumed area of evolution or original home of even the 
most ancient and ])rimitive genus or species as being where its 
j)resent-day metropolis is placed, from whence they are assumed to 
be extending their range, but to which they are indissolubly bound, 
as that author in his famous memoir describes the relative geo- 
graphical positions of the various European floras he distinguished 
and though his argument is essentially based upon migration or 
dispersal he has reasr)ned from the present day position of the con- 
stituent species of his various regions and assumed them to be 
una fleeted and unaltered by the enormous changes that have taken 
place since Miocene times. 
