A Period in the History of our Planet. 7 



of life to the conclusion of the coal period^ in which, no doubt, 

 three periods might be distinguished, during which fish ap- 

 pear as the highest development of animal life. In like 

 manner, I comprehend the collective series of strata, from 

 the Bothliegendes to the Muschelkalk and Keuper — the series 

 of the trias formations — as a second grand epoch ; the Jurassic 

 period^ with all its subdivisions, as a third; the chalk as a 

 fourth grand epoch — three periods in which tho ugly race of 

 reptiles gains the upper hand, and presents itself at the sum- 

 mit of creation ; and, lastly, the tertiary period, and the sub- 

 sequent epoch of what is called the dilwcial formations ^ in the 

 course of which the mammiferous animal gradually acquires its 

 present conformation, and paves the way for the creation of 

 man and the race of beings that now encircle him. 



Whatever may have been the original form of the earth, 

 every thing indicates that, when the first organic creation en- 

 livened its surface, the latter was overflowed with widely ex- 

 tended but shallow seas, from which emerged only a few is- 

 lands, scarcely elevated above the surface of the waters. K 

 wonderful animal creation inhabited these oceans ; vegetable 

 organisms, no less striking, covered the marshy land. The 

 uncouth Orthoceratites, huge cuttle-fish, trailing after them 

 the shells which serve as their dwellings for a year, with their 

 tiny kindred, the unnumbered heaps of Goniatites ; quantities 

 of complexly organized Terebratulse (which have hitherto been 

 placed in a class by themselves, but improperly, as they may 

 be regarded as merely a peculiar family, though the lowest, of 

 the class of Acephala) ; grotesquely formed Polypi and Encri- 

 nites, attached to the shallow beaches, present themselves as 

 the earliest organisms in the two great types of molluscous 

 and radiated animals. The series of the articulated animals, 

 the dead remains of which, no doubt, had no such solid por- 

 tions to oppose to corruption as the animals of other classed, 

 finds itself, however, represented by scorpions and the strange 

 Trilobites. How anomalous the form of these fossil crabs was, 

 as compared with the order of Entomostraca, is apparent from 

 the circumstance that naturalists did not know for long what 

 to make of their bodies, until a more exact comparative in- 



