150 FORMATION OF CORAL REEFS. 



that prepared the earth for the coming of man, 

 and the animals and plants that accompany him 

 on earth, baffles our finite attempts to estimate 

 its duration, have we any means of determining 

 even approximately the length of the period to 

 which we ourselves belong? If so, it may fur- 

 nish us with some data for the further solution 

 of these wonderful mysteries of time, and it is 

 besides of especial importance with reference to 

 the question of permanence of Species. 



Those who maintain the mutability of Species, 

 and account for all the variety of life on earth 

 by the gradual changes wrought by time and 

 circumstances, do not accept historical evidence 

 as affecting the question at all. The relics of 

 those oldest nations, all whose history is pro- 

 served in monumental records, do not indicate 

 the slightest variation of organic types from the 

 earliest epoch to this day. The. animals pre- 

 served within their tombs or carved upon the 

 walls of their monuments by the ancient Egyp- 

 tians were the same as those that have their 

 home in the valley of the Nile to-day ; the 

 negro, whose peculiar features are unmistaka- 

 ble even in their rude artistic attempts to rep- 

 resent them, was the same woolly-haired, thick- 

 lipped, flat-nosed, dark-skinned being in the 

 days of the Rameses that he is now. The 

 Apis, the Ibis, the Crocodiles, the sacred Beetles, 



