PREFACE. 
XV 
on this subject in a paper in the number of the Edinburgh 
Philosophical Journal, entitled “ Remarks illustrative of the In- 
fluence qf Society on the Distribution of British Animals!'’' 
Other observers, undervaluing the cause of extinction here assign- 
ed, have imagined, that the species referred to were destroy- 
ed by the agency of a violent Deluge, which they consider as 
identical with the one recorded by Moses. How this deluge 
could select a few species only as the objects of its vengeance, 
and leave in safety many species living in the same regions, and 
possessing nearly the same habits, is a difficulty which the abet- 
tors of the hypothesis have not yet ventured to explain. Should 
they attempt to account for the safety of the existing races, by 
supposing that they were preserved in the Ark, they have still 
to find proof of the law of exclusion, under the operation of 
which the now extinct kinds were denied protection. The ex- 
travagant pretensions of this hypothesis have been pointed out 
by the author, in a paper inserted in the S8th number of the 
Edinburgh Philosophical Journal, entitled “ The Geological 
Deluge^ as interpreted by Baron Cuvier and Professor Buck- 
land^ inconsistent with the Testimony of J/oses, and the Phe- 
nomena of Nature^ 
Among the extinct animals there are multitudes of species, 
the relics of which do not occur in the superficial strata, and 
are never associated with the remains of the extirpated or exist- 
ing kinds. These are found imbedded in solid rock, and seem 
to have occupied the surface of the earth, when its physical 
condition and animal and vegetable productions differed greatly 
from the present order of things. By attending to the specific 
marks of these remains, the manner in which they are associat- 
ed, and the strata in which they are imbedded, it is easy to dis- 
cover that they do not all possess claims to the same degree of 
antiquity, and that they may be distributed into certain well 
marked Zoolog'ical Epochs. In the arrangement of the strata, 
inclosing these organic remains, there is a definite order of su- 
perposition, and there are characters likewise marking groups of 
different degrees of antiquity. Hence has arisen the idea of 
Geological Epochs, first distinctly intimated by Lister and 
Stenon, and elucidated by a host of subsequent observers. 
