FUNDAMENTAL RELATIONS OF ANIMALS 115 



veloped into an organ of flight, or assuming in other families the 

 shape of a fin, as in the Whale, or the Sea-turtle, in which the close 

 connection of the fingers is carried out to another extreme. 



Without entering into further details upon this subject, which will 

 be fully illustrated in my Contributions to the Natural History of 

 the United States, enough has already been said to show that the 

 leading thought which runs through the succession of all organized 

 beings in past ages is manifested again in new combinations, in the 

 phases of the development of the living representatives of these differ- 

 ent types. It exhibits everywhere the working of the same creative 

 Mind, through all times, and upon the whole surface of the globe. 



SECTION XXVI 

 PROPHETIC TYPES AMONG ANIMALS 



We have seen in the preceding Section, how the embryonic con- 

 ditions of higher representatives of certain types, called into exist- 

 ence at a later time, are typified, as it were, in representatives of the 

 same types which have existed at an earlier period. These relations, 

 now they are satisfactorily known, may also be considered as exem- 

 plifying, as it were, in the diversity of animals of an earlier period 

 the pattern upon which the phases of the development of other ani- 

 mals of a later period were to be established. They appear now, like 

 a prophecy in those earlier times, of an order of things not possible 

 with the earlier combinations then prevailing in the animal king- 

 dom, but exhibiting in a later period, in a striking manner, the an- 

 tecedent considerations of every step in the gradation of animals. 



This is, however, by no means the only nor even the most remark- 

 able case of such prophetic connections between facts of different 

 dates. 



Recent investigations in Palaeontology have led to the discovery 

 of relations between animals of past ages and those now living which 

 were not even suspected by the founders of that science. It has, for 

 instance, been noticed that certain types which are frequently prom- 

 inent among the representatives of past ages combine in their struc- 



