GEOLOGICAL RECORD. 69 
classes, and, in the case of AZammalia, the past history of 
some orders has by this means been largely unravelled. If 
the progress of evolution has been from lowest to highest 
this is exactly the state of affairs we should expect to find, 
We may tabulate the classes and the order of their 
appearance in time. 
Eocene........... 
Jurassic........... 
Triassic........... 
Classes or 
Phyla. 
(Man.).. .... 
Amphibia........ 
Reptilia 
Birds-.cvscsee aes 
Mammalia 
Arthropoda ...... 
Mollusca ......... 
PISCESsieainsicren sas 
Brachiopoda..... 
Annulata ........ 
Porifera........... 
Coelenterata ..... 
Echinodermata... 
The geological record must therefore be regarded as 
merely a last chapter of the history of creation, a chapter 
with enormous imperfections and numerous omissions, 
written in a language which is capable of many delineations 
