/if AJNT SINGLE FORMA TION. 33 1 



certain sea-shells inhabiting the shores of North America, 

 which are ranked by some conchologists as distinct species 

 from their European representatives, and by other con- 

 chologists as only varieties, are really varieties, or are, as 

 it is called, specifically distinct. This could be effected 

 by the future geologist only by his discovering in a fossil 

 state numerous intermediate gradations; and such success 

 is improbable in the highest degree. 



It has been asserted over and over again, by writers who 

 believe in the immutability of species, that geology yields 

 no linking forms. This assertion, as we shall see in the 

 next chapter, is certainly erroneous. As Sir J. Lubbock 

 has remarked, '' Every species is a link between other allied 

 forms." If we take a genus having a score of species, 

 recent and extinct, and destroy four-tifths of them, no one 

 doubts that the remainder will stand much more distinct 

 from each other. If the extreme forms in the genus 

 happen to have been thus destroyed, the genus itself will 

 stand more distinct from other allied genera. What geo- 

 logical research has not revealed, is the former existence of 

 infinitely numerous gradations, as fine as existing varieties, 

 connecting together nearly all existing and extinct species. 

 But this ought not to be expected ; yet this has been 

 repeatedly advanced as a most serious objection against 

 my views. 



It may be worth while to sum up the foregoing remarks 

 on the causes of the imperfection of the geological record 

 under an imaginary illustration. The Malay Archipelago 

 is about the size of Europe from the North Cape to the 

 Mediterranean, and from Britain to Kussia ; and therefore 

 equals all the geological formations which have been 

 examined with any accuracy, excepting those of the United 

 States of America. I fully agree with Mr. God win- Austen, 

 that the present condition of the Malay Archipehigo, with 

 its numerous large islands separated by wide and shallow 

 seas, probably represents the former state of Europe, 

 while most of our formations were accumulatiusx. 'I'he 

 Malav Archipelago is one of the richest regions in organic 

 beings; yet if all the species were to be collected which 

 have ever lived there, how imperfectly would they repre- 

 sent the natural history of the world ! 



But we have every reason to believe that the terrestrial 



