Miscellanies. 415 
In the 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 isremarka- 
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 Miccaxe,4 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 living species 
is so very decided.’ The former includes the Sub-appenine as and 
the English Crag ; the latter the Sicilian beds. 
Tt has been stated that forty five hundreths of the species found. 
in the English crag exist in a recent state ; while in the Sicilian 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 reliquiz, 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 ‘ 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 
eee 
* Principles of Geology, Vol. 3. p. 55. 
