136 STUDIES IN LIFE AND SENSE. 



interpretation of the history of the Deluge ; and with the establish- 

 ment of the existence of distinct provinces of distribution, any 

 serious belief in the peopling of the world by migration from 

 Mount Ararat came to an end. Under these circumstances, only 

 one alternative was left for those who denied the occurrence of 

 evolution namely, the supposition that the characteristic animals 

 and plants of each great province were created as such within the 

 limits in which we find them. And as the hypothesis of ' specific 

 centres ' thus formulated was heterodox from the theological 

 point of view, and unintelligible from the scientific aspect, it may 

 be passed over without further notice as a phase of transition 

 from the creational to the evolutional hypothesis. In fact," adds 

 Huxley, " the strongest and most conclusive arguments in favour of 

 evolution are those which are based upon the facts of geographical, 

 taken in conjunction with those of geological, distribution." 



Or if we turn for a moment to the opinion of Mr. Darwin him- 

 self, we shall find an equally clear expression of the futility of the 

 attempt to explain distribution on any other save an evolutionary 

 understanding. In his classical work, the "Origin of Species,'* 

 Darwin remarks the fact that " neither the similarity nor the dissimi- 

 larity of the inhabitants of various regions can be wholly accounted 

 for by climatal and other physical conditions." He secondly notes 

 the fact, " that barriers of any kind, or obstacles to free migration, are 

 related in a close and important manner to the differences between 

 the productions of various regions ; " and a third fact noted by 

 Darwin is " the affinity of the productions of the same continent or 

 of the same sea, though the species themselves are distinct at different 

 points and stations." Again, Darwin remarks that, " in discussing 

 this subject we shall be enabled at the same time to consider a 

 point equally important for us, namely, whether the several species of 

 a genus, which must on our theory all be descended from a common 

 progenitor, can have migrated, undergoing modification during their 

 migration, from some one area. If, when most of the species 

 inhabiting one region are different from those of another region, 

 though closely allied to them, it can be shown that migration from 

 the one region to the other has probably occurred at some former 

 period, our general view will be much strengthened, for the explana- 

 tion," adds Darwin, "is obvious on the principle of descent with 

 modification. A volcanic island, for instance, upheaved and formed 

 at the distance of a few hundreds of miles from a continent, would 

 probably receive from it in the course of time a few colonists, and 

 their descendants, though modified, would still be related by inherit- 

 ance to the inhabitants of that continent. Cases of this kind are 

 common, and are, as we shall hereafter see, inexplicable on the theory 

 of independent creation." 



