ITS CLOSE. 117 



their impress on the life of that era. So also with its 

 sauroid fishes ; and so also with many genera and species 

 of its shell-fish and corals and encrinites, which though 

 more lowly are nevertheless peculiarly distinctive of car- 

 boniferous seas, and are never found in the waters of sub- 

 sequent ages. 



From the first to the last from the Silurian to the Per- 

 mian all has been growth and decay, and in that death a 

 progress which ever goes forward without halt or hesitation. 

 No indecision ; no trial-work ; no error to be corrected ; 

 no blunder to be revised. And yet amid all this incoming 

 and outgoing, as we shall see in the following chapter, 

 there has been no break in vitality, no change of the 

 great primal patterns, but merely such modifications as 

 best harmonise with the new conditions of each succeeding 

 era. Nor must we regard this harmony between geographi- 

 cal condition and organic manifestation in any other light 

 than that of a mere co-adaptation ; for over and above it there 

 is clearly a prescient design, having respect to development 

 in time from more general to more specialised types, and from 

 physiological simplicity to physiological complexity of func- 

 tions. From the obscure and simple forms of the lowest 

 stratified systems we rise stage after stage to higher and 

 higher manifestations of life ; onwards and, still upwards is 

 the orderly course of creation ; and yet in this vast and 

 varied progression every member is bound to that which 

 preceded it, as well as to that which accompanies it, by the 

 ties and relationship of one great cosmical plan. This is 

 surely more than mere " physical development" some- 

 thing higher than the " transmutation of specific forms 

 under the force of external conditions" something more 

 precise and definite than " natural selection in the struggle 

 for existence," or any other of the materialistic hypotheses 



H 



