124 
THE GROWTH OF CONTINENTS. 
not only by the gradual accumulation of mate* 
rials, but also by the upheaval of large tracts of 
stratified deposits ; for, though the loftiest moun- 
tain-chains did not yet exist, ranges like those 
of the Alleghanies and the Jura belong to this 
division of the world’s history. During this time, 
the general character of the animal and vegetable 
kingdoms was higher than during the previous 
age. Reptiles, many and various, gigantic in 
size, curious in form, some of them recalling the 
structure of fishes, others anticipating birdlike 
features, gave a new character to the animal 
world, while in the vegetable world the reign of 
the aquatic Cryptogams was over, and terrestrial 
Cryptogams, and, later, Gymnosperms and Mono- 
cotyledonous trees, clothed the earth with foliage. 
Such was the character of this second age, from 
its opening to its close ; and though there are 
indications that, before it was wholly past, some 
low, inferior Mammalian types of the Marsupial 
kind were introduced,* and also a few Dicotyle- 
donous plants, yet they were not numerous or 
* I say nothing of the traces of Birds in the Secondary de- 
posits, because the so-called bird-tracks seem to me of very 
doubtful character; and it is also my opinion that the remains 
of a feathered animal recently found in the Solenliofen litho- 
graphic limestone, and believed to be a bird by some naturalists, 
do not belong to a genuine bird, but to one of those synthetic 
types before alluded to, in which reptilian structure is combined 
with certain birdlike features. 
