384 Scientific Intelligence.' — Geology. 



those of Mont-Dore. This deposit is interrupted by a bed of 

 rolled pebbles ; it forms the platform which crowns the moun- 

 tain of Perrier. Under this deposit, which contains bones, there 

 is a thick bed of pebbles of a large size, volcanic and primitive, 

 of from three to four metres thick, which rests immediately up- 

 on the limestone deposited in fresh water-lakes, the strata of 

 which contain, along with other remains of animals, a multitude 

 of shells analogous to those which live, at the present day, in 

 our marshes and brooks. The bones of this latter deposit, 

 which is the oldest in the order of time, belong to genera which 

 no longer exist on the earth, and to species of genera still exist- 

 ing, but which are themselves extinct. They belong to lophio- 

 dons, anaplotheria, civets, species of the genus lagomys, fresh- 

 water tortoises, crocodiles, and serpents. Among them are eggs 

 perfectly preserved, and skeletons of birds. The more modern 

 deposit contains bones of tapirs, elephants, rhinoceroses, horses, 

 hippopotami, mastodons, beavers, dogs, mice, of several large 

 cats, tigers, panthers, and eleven or twelve different species of 

 the deer kind. All these bones completely retain their original 

 form, even their chemical nature has been little altered ; for they 

 contain thirty-six parts of phosphate of lime, and seven of animal 

 matter. 



16. Teneriffe Filtering Stone.— The filtering stone of Tene- 

 riff is one of those modern calcareous formations described by 

 Dr Fitton, in his interesting geological view in Captain King's 

 Voyage. Von Buch, in his Geology of the Canary Islands, de- 

 scribes the filtering stone as daily forming on the sea-shore, by 

 the agglutination of broken shells, and fragments of trachyte 

 and basalt, by means of a calcareous sinter deposited from the 

 comparatively hot sea-water of the tropical seas ; and most of the 

 grains of the rock thus formed have a calcareous crust, formed 

 around a nucleus of trachyte, basalt, or fragments of shells, and 

 the whole much resembles oolite or roestone. He adds, " Since I 

 witnessed the formation of the filtering stone, I do not deny that 

 the oolite of the Jura limestone may have been formed by agi- 

 tation, in warm water, of fragments of shells ; and I doubt not 

 that beds of oolite may, even now, be depositing in this way on 

 tlve coral banks of the tropical regions." In Captain Campbell's 



