OF CREATION. 259 



found in any of the intermediate deposits. Just so 

 it is with the mammals. In the lower beds of the 

 middle part of the series we have a few but distinct 

 traces of their presence ; these, however, are totally 

 lost in the newer beds, and even in the Weald, a 

 fresh-water deposit, we are still without a single frag- 

 ment that can be supposed to have belonged to any 

 quadruped, the companion on land of the gigantic 

 dinosaurians. 



The Invertebrata illustrate the same fact yet more 

 decisively. A vast development of the highest 

 type, the Cephalopoda, seems to have been through- 

 out characteristic of the period, and one genus alone, 

 that of ammonites, was represented then by many 

 more species that now form the whole group. The 

 belemnites and other free-swimming animals of the 

 same kind (cuttle-fish) were no less abundant, and 

 their remains are found every where, distributed 

 it is true locally, owing to the conditions of de- 

 posit being only occasionally favourable for their 

 preservation. Other univalve shells are also met 

 with in great abundance, proving clearly how similar 

 the conditions of existence must have been to those 

 which still obtain in various parts of the world. 

 The abundance of Terebratulae in particular locali- 

 ties, the presence of other bivalve shells of almost 

 all the different existing families, the development 

 of Foraminifera and minute infusorial animalcules in 

 deep sea deposits, and, indeed, almost every natural 

 history fact presented to us, offers the strongest ana- 

 logy to similar facts now observable. These facts 

 all prove how greatly the study of existing nature 

 may aid us in working out the problems of the past 



