SPECIAL CREATION OR DERIVATION? 



hymenoptera range over large tracts of inland 

 country, but are stopped by such obstacles as 

 the Straits of Gibraltar. On opposite sides of 

 the Andes, the conditions of existence differ 

 but little, while on the north and south sides 

 of the Caucasus the difference in climate is ex- 

 treme. Yet the Andes are much the more diffi- 

 cult to cross, and accordingly the fauna which 

 they separate are much more unlike than the 

 fauna separated by the Caucasus. In like man- 

 ner the Galapagos Islands, situated some six 

 hundred miles from the South American con- 

 tinent, possess a fauna which, with the excep- 

 tion of a few birds, is generically distinct from 

 all other faunas. Yet though generically distinct, 

 it is South American in type, and most resem- 

 bles the fauna of Chili, the nearest mainland. 

 Furthermore, among the animals living on the 

 different islands of the group, we find specific 

 diversity along with generic identity. So also 

 Madeira " is inhabited by a wonderful number 

 of peculiar land-shells, whereas not one species 

 of sea-shell is peculiar to its shores." Similar 

 relations are found universally to hold between 

 the organisms which inhabit oceanic islands 

 and those which inhabit neighbouring con- 

 tinents. 



These facts of geographical distribution, when 

 taken in connection with the facts of geologi- 

 cal succession above mentioned, speak very em- 

 409 



