III.] CONCLUSION. 143 



dant on the opposite side of the equator. The practical absence 

 of mammals from the Galapagos Islands is of little import one 

 way or the other, as they might have been drowned out during the 

 subsidence; but perhaps, on the whole, a suspension of judgment 

 as to the relation of these islands to the mainland is the wisest 

 course to adopt at present. 



Finally, whether the hypotheses that have been advanced in 

 the present chapter to explain the origin of the peculiar mammalian 

 fauna of Neogaea be substantiated or the reverse, there can be 

 little doubt that Dr Wallace has been misled in his statement 

 that this area, so " far as we can judge from the remarkable 

 characteristics of its fauna and the vast depths of the ocean east 

 and west of it, has not during Tertiary, and probably not even 

 during Secondary times, been united with any other continent, 

 except through the intervention of North America." 



