Miscellanies. 415 



" In ihe lowest of these, the Eocene period there have been ob- 

 served in Europe, one thousand, two hundred and thirty eight spe- 

 cies; of which the very small number, of forty two, have been identi- 

 fied with recent species. Of fossil species not known as recent, forty 

 two are common to the Eocene and Miocene epochs.* It is remarka- 

 ble too, that the living species are rarely the inhabitants of the shores 

 of those countries in which they are found in a fossil state, inhabi- 

 ting now more southern climates. 



" The next period of deposit, that of the Miocene, is a formation 

 distinct in its characters from the London clay below, and the Eng- 

 lish Crag above it. In it, M. Deshayes, has observed one thou- 

 sand and twenty one species, one hundred and seventy six of which 

 are found in a recent state. 



" Superior again to this in the Pliocene period, we find the recent 

 species comparatively abundant. Mr. Lyell, in dividing this into 

 older and newer Pliocene, observes, ' the plurality of Uving species 

 is so very decided.' The former includes the Sub-appenine hills and 

 the English Crag ; the latter the Sicilian beds. 



" It has been stated that forty five hundreths of the species found 

 in the English crag exist in a recent state ; while in the Sicihan beds, 

 according to Mr. Lyell, ten only out of two hundred and twenty six 

 are extinct, or unknown, nearly the whole of them existing at the 

 present time in the neighboring seas. 



In addition to the marine reliquiae, the remains of terrestrial mam- 

 miferous animals afford us, in the tertiary formation, a striking proof 

 of the extraordinary change which has taken place. Of the nume- 

 rous species, the remains of which are there found, none now exist. 

 More than forty of the Eocene mammifers, are referable to a division 

 of the order Pachydermata, which has now only four living represen- 

 tatives on the globe ; of these not only the species but the genera, 

 are distinct from any of those which have been established for the 

 classification of living animals. " The mammalia of the Miocene 

 agree in some of the genera with recent animals, and those of the 

 Pliocene are an intermixture of extinct and recent species of quad- 

 rupeds." 



Superior and next to the tertiary is De la Beche's erratic block 

 group, and above it, his modern group. These two are embraced 

 in Mr. Lyell's recent period, and here are found to exist the remains 



* Principles of Geology, Vol. 3. p. 55. 



