GEOGENY. 



servation alone enables us to add a great number of details, 

 useless no doubt to most men, but interesting at least to the smaL 

 number of those who dedicate themselves to study, if indeed 

 they are not destined perhaps to enlighten their belief. 



The assemblage of data we now possess leads us to perceive 

 that each of the particular -creations briefly indicated in Genesis, 

 with the exception of that of man, did not take place in a single 

 moment ; that, on the contrary, it was successively, in a considera- 

 ble space of time, and in proportion as the terrestrial globe itself 

 was fashioned. Indeed, if the vascular cryptoga'mia appeared 

 nearly from the commencement of things, the gy'mnospe'rmous 

 phaneroga'mia did not appear until about the epoch of the coal 

 formation, and did not exist in abundance until long afterwards ; 

 it is the same with the monocoty'ledons, the remains of which are 

 at first few and indistinct, and not clearly seen until after the chalk ; 

 the dicoty'ledons did not appear until strtl later, in the midst of the 

 tertiary formations. In all this interval of time, the species suc- 

 cessively changed, and those which were created, have in turn also 

 entirely disappeared, one after the other, to give place to the 

 new. 



Fishes, reptiles and mollusks, respectively present us with the 

 same phenomena, and still more clearly show the successive ex- 

 tinctions of different races, and the appearance of many others. 

 The sauroid fishes, which lived at the time that coal was formed in 

 Belgium and England, disappeared for ever in the new order of 

 things, established in the penine formation. True sharks did not 

 exist then, but appeared long after in the creta'ceous sea. Gigan- 

 tic saurians, with paws in form of paddles, and flying saurians, 

 existed in abundance in the jura'ssic epoch, but disappeared in 

 the following period, and were replaced in it by enormous ter- 

 restrial saurians. of which there are no previous traces, and, after 

 long having inhabited the earth by themselves, the latter were 

 also successively lost, leaving only crocodiles after them, still very 

 different from those of the present day. The same is true of the 

 tri'lobites, produclus, and spi'rifers, which, after having multiplied 

 for some time, disappeared one after the other. The ammonites and 

 belemnites succeeded them, and are found in abundance in the 

 jura'ssic sea ; then they became completely extinct, after having 

 successively changed species, at the moment in which the chalk 

 formation ceased to take place. All the mollusks that followed 

 after, more and more resemble those now existing, of which there 

 was then no trace. 



Mammals present themselves under similar circumstances ; the 

 different orders and different species appeared only in succession. 

 The first were only the feeble marsupials. Long afterwards came 

 the pachyderms, analogous to the tapir, the first species of which 



