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Revie ws and Notices of Books. 



graphy, and which extended observation in geology refuses to 

 confirm. As a general maxim, it is true that the most trust- 

 worthy tests of the sequence of the stratified systems are the fossil 

 organisms which these systems contain. It is also true, that over 

 limited tracts like Britain, or even over the area of Europe, con- 

 temporaneous deposits are characterised by the same fossil spe- 

 cies ; but it may not be true that the same species never recur at 

 more stages than one in the same formation, nor may it be true 

 that formations containing the same species in widely separated 

 regions are strictly contemporaneous. The truth is, there has 

 been a tendency of late to carry the argument of fossil evidence 

 beyond its legitimate limits. Under the change of external con- 

 ditions, a species— say a marine one — may gradually shift its 

 ground many degrees south or north, and so become extinct in its 

 original area, and yet, after hundreds of feet of sediment had been 

 deposited on that area, a reversal of conditions may occur, and 

 establish the species once more on its primal habitat. We would 

 thus have the same species occurring at two different stages of the 

 same great formation, separated, it may be, by some thousands of 

 years in time, though only by a few hundred feet of sediment. 

 Again, under the slow oscillation of sea and land, species terrestrial 

 and marine may have been gradually transferred from the latitudes 

 and longitudes of Europe to the latitudes and longitudes of America; 

 and thousands of years after they had become fossil in the eastern 

 hemisphere, they may have been flourishing in the western." 



After considering the appearance of life on the globe, the author 

 calls attention to the theory of Progression, and more espe- 

 cially discusses the Darwinian views as to external condition, 

 embryonic phases, use and disuse of organs and natural se- 

 lection, and he concludes that all these " are but subordinate 

 factors of one great law, and that we must know much more of 

 the forms that have become extinct, and more of the variations 

 that are now taking place in existing plants and animals before 

 we can hope to approach the solution of the all-important problem." 



The origin of man naturally becomes a matter of consideration. 

 On this point the author says : — 



" Whatever be the plan of development, it must of necessity 

 embrace the whole scheme of vitality. There can be no severance 

 in the great creational idea of life ; and whatever theory be 

 adopted, it must be applicable alike to every constituent member 

 of the system. The highest as well as the lowest, man as well as 

 the monad, forms part and parcel of one continuous evolution ; 

 and whatever the ordainings of the past, they exist in the present, 

 and must operate in the future. If by any genetic law the radiata 

 have given birth to the articulata, the articulata to the mollusca, 

 and the mollusca to the vertebrata — nay,- were it only the great 



