OF CREATION. 55 



cession of animals which the pursuit of Geology has 

 proved to exist. It should, however, be clearly un- 

 derstood, that, in making use of this term " succes- 

 sion," I have no intention of assuming a gradual mo- 

 dification of species in the way of the development of 

 a higher organization, as if animals originally created 

 imperfect were subsequently, and by manifest grada- 

 tion, at length enabled to perform functions of a higher 

 kind ; for this is by no means the case, so far as the 

 observations of Geologists have hitherto been able to 

 determine. The order of nature seems rather to be a 

 succession of this kind ; namely, that first of all, as we 

 have seen in the last chapter, representatives were in- 

 troduced of each of the principal natural subdivisions 

 of the invertebrated animals, combining many typical 

 characteristics subsequently kept separate, and that 

 the species thus originally introduced were gradually 

 displaced by others in which distinctness of typi- 

 cal character was more marked. Some animals, as 

 the coral polyps, remained stationary in point of 

 development ; others, as the encrinites, lasted for a 

 long time, but at length were partly superseded by 

 higher types of the group, performing offices which 

 required greater powers of locomotion; others, again, 

 as the brachiopods, exhibited almost immediately the 

 greatest abundance, variety, and extent of their de- 

 velopment, and were only superseded, after a long 

 interval, by the higher conchifers, which at first were 

 sparingly introduced ; while, again, others, (and those 

 the most important in every respect,) such as the 

 Cephalopoda, at once assumed an importance which 

 hardly increased, although it varied, for a long period, 

 and at length actually became less ; these animals 



