48 ON TIIK STUDY OF ZOOLOGY 



to genera, entirely new to us. One of these, an elephant, 

 specifically distinguishable both from that of Asia and Africa, 

 has been met with in most parts of Europe, in countries 

 and climates where no animal of the kind has ever been 

 known in a living natural state, and in which the known 

 species, inhabitants of the torrid zone, would be speedily 

 destroyed. The fossile shells differ more or less from those 

 of living species. In many places, several successions of 

 fresh and salt water strata are discovered, indicating suc- 

 cessive revolutions in the earth's surface, under the action 

 of causes differing from each other in their nature. The 

 inferior layers, or the first in order of time, contain the re- 

 mains most widely different from the animals of the living 

 creation ; and, as we advance to the surface, there is a 

 gradual approximation to our present species. 



These examinations have furnished almost the only ac- 

 curate data for any reasonable conclusions respecting the 

 number, nature, and progressive series of the changes which 

 have affected the earth's surface — of the pre-adamitic revo- 

 lutions of the globe ; and they suggest matter for curious 

 speculation respecting the extinct races of animals, and the 

 mode in which their place has been supplied by the actual 

 species of living beings. The writings of Cuvier, Brong- 

 NiART, and Lamarck, in France, and of Mr. Parkinson, 

 in this country, will give you the best information on this 

 new kind of antiquarian research, on these authentic me- 

 morials of beings, whose living existence must be carried 

 beyond the reach of history and tradition — beyond even 

 the fabulous and heroic ages, and has been supposed, with 

 considerable probability, to be of older date than the for- 

 mation of the human race. 



Another important branch of the physical history of the 

 globe belongs to zoology ; I mean, the nature, origin, and 

 progress of the banks, reefs, and rocks of coral, and even 

 the islands, which are perpetually arising and accumulating 

 in the intertropical seas. These vast masses of calcareous 

 matter are aggregated by the slow but incessant operations 

 of countless millions of minute beings, so small, and so 



