Ch. XV.] UPPEE EOCENE FORMATIONS. 183 



having two pair of horns resembling those of antelopes. The number of 

 species of the genus Antelope is also remarkable. In the same fauna 

 appear many carnivorous beasts, often belonging to existing genera, and 

 several species of monkey. Among the reptiles are crocodiles, some 

 larger than any now living ; and an enormous tortoise, Testudo Atlas^ the 

 curved shell of which measured twenty feet across. 



CHAPTER Xy. 



UPPER EOCENE FORMATIONS. 



{Lower Miocene of many authors?^ 



Preliminary remarks on classification, and on the line of separation between 

 Eocene and Miocene strata — Whether the Limburg and contemporaneous for- 

 mations should be called Upper Eocene — Limburg strata in Belgium — Strata 

 of same age in North Germany — Mayence basin — Brown Coal of Germany — 

 Upper Eocene of Hempstead Hill, Isle of Wight — Upper Eocene of Erance — 

 Lacustrine strata of Auvergne — Indusial limestone — Freshwater strata of the 

 Cantal — Its resemblance in some places to white chalk with flints — Proofs of 

 gradual deposition — Upper Eocene of Bourdeaux, Aix-en-Provence, Malta, <fec. 

 — Upper Eocene of Nebraska, United States. 



Preliminary re^narks. — In the last chapter it was stated that as yet we 

 know of no marine strata in the British Isles contemporaneous with the 

 faluns of Touraine, or those shelly deposits of the valley of the Loire 

 which I selected as the type of the Miocene period. There have, how- 

 ever, been recently discovered in the Isle of Wight certain fluvio-marine 

 deposits, which many continental geologists would call " Lower Miocene," 

 the " faluns" being termed by them " Upper Miocene." A few prelimi- 

 nary remarks on this difference of nomenclature, bearing as it does on 

 questions involving the first principles of classification, will be necessary 

 before I treat of the Upper Eocene formations. 



The marine strata, which in the north of France come next in chrono- 

 logical order to the " faluns," or which immediately precede them in age, 

 are the sands and sandstones, called the " Gres de Fontainebleau," or 

 "sables marins superieurs." (See General Table, p. 104.) They consti- 

 tute the uppermost beds of the Paris basin, and are overlaid by a fresh- 

 w^ater limestone called " Calcaire de la Beauce." The upper marine sands 

 sontain no fossil shells common to the faluns, or extremely few species ; 

 and no shells of living species, or, if so, they are about as scarce as in the 

 Middle or typical Eocene groups. In consequence of this distinctness in 

 the fossils, and for other reasons presently to be mentioned, I excluded 

 these " upper sands" from the Miocene period in former editions of this 

 work, availing myself of the hiatus between the Gres de Fontainebleau 

 and the faluns to draw a line of separation between Eocene and Miocene, 



