CHAPTER VII. 



SPECIES AND SPACE. 



The geographical distribution of animals presents difficulties. These not 

 insurmountable in themselves ; harmonize with other difficulties. 

 Fresh-water fishes. Forms common to Africa and India ; to Africa and 

 South America ; to China and Australia ; to North America and China ; 

 to New Zealand and South America ; to South America and Tas- 

 mania ; to South America and Australia. Pleurodont lizards. Insec- 

 tivorous mammals. Similarity of European and South American frogs. 

 Analogy between European salmon and fishes of New Zealand, &c. 

 An ancient Antarctic continent probable. Other modes of accounting 

 for facts of distribution. Independent origin of closely similar forms. 

 Conclusion. 



THE study of the distribution of animals over the earth's 

 surface presents us with many facts having certain not 

 unimportant bearings on the question of specific origin. 

 Amongst these are instances which, at least at first sight, 

 appear to conflict with the Darwinian theor^of " Natural 

 Selection." It is not, however, here contended that such 

 facts do by any means constitute of themselves obstacles 

 which cannot be got over. Indeed, it would be difficult 

 to imagine any obstacles of the kind which could not be 

 surmounted by an indefinite number of terrestrial modi- 

 fications of surface submergences and emergences 

 junctions and separations of continents in all directions, 

 and combinations of any desired degree of frequency. 



