1^4 EXPLANATIONS. 



are decidedly peculiar. The same holds good 

 regarding the shells and the insects. Here we 

 have the terrestrial animals spreading out into 

 numerous variations, according to the greater 

 variety, and the more peculiar character, of the cir- 

 cumstances determining their organization.* Mr. 

 Darwin has likewise observed such facts in the 

 natural history of solitary islands, as induce him 

 to express his belief, that " the leaders, after the 

 innumerable iceb-footed species, are generally the first 

 colonists of small islands.'''' It is his supposition, 

 that the birds in those instances are immigrants ; 



reasoning we have never met with." Assuredly it may well be 

 held up, as that Review holds it, " as a warning to believers in 

 ex parte criticism." The fact is, since, as Professor Phillips admits, 

 there has been no break in the chain of life from the beginning, 

 our other continents, whatever minor changes they may have 

 undergone, have continued without any entire submergence since 

 at least the commencement of terrestrial life. They are, there- 

 fore, older than Australia could be presumed to be, even upon 

 the principle hinted at by the Edinburgh reviewer. But is not 

 that principle utterly absurd, implying as it does that life had 

 stood still in Australia at one point, while it was advancing to the 

 highest forms in other countries? Nay, that the agencies em- 

 ployed in the formation of rocks had been stopped there, for 

 perhaps a third of the time of the earth's existence? The note 

 would not be worthy of this analysis, but that the self-complacency 

 of the writer is so apt to impose upon readers who do not inquire 

 for themselves. 



* See Darwin's Journal of a Voyage Round the World, c. xvii. 



