324 NATURAL SCIENCE [November 
Secondly. In the last sentence I commenced with a very large 
“Tf” because I am afraid my heretical perversity carries me a good. 
deal further than I have yet dared to admit. 
Before Herbert Spencer held up his great lamp and bade us see 
in animal and vegetable life not a discrete collection of disintegrated 
units but a continuous unbroken chain, it was prudent and wise 
perhaps to be content with an arrangement of the stratified beds 
marked by no other law or rule than their mere order of super- 
position in any particular place. This will no longer content us. 
We want to know a great deal more than this. We want to know 
what was the route and road by which a particular fauna and flora 
came to occupy a particular zoological or botanical province, 
and what were the stages of its growth and development. For 
this supreme purpose we must go further afield than merely 
examine the column of strata existing in any particular place. A 
very cursory examination at once shows us that in every such 
column marine beds are intercalated with sub-aerial beds, and no 
ingenuity can possibly derive the fauna of the land from that of 
the sea and wice versd by successive jumps and starts. They have 
absolutely nothing to do with each other, and if our purpose is not 
merely to calendar the revelutions of land and sea which have 
oceurred in a particular place, but to trace out the history of the 
particular fauna occupying a particular province, either of the land 
or of the sea, and thus to track the continuous history of each of 
these divergent portions of the earth’s surface along lines of con- 
tinuity and growth, we must absolutely discard our present method 
of geological arrangement and nomenclature for a very different one. 
In the first place (and the change is so obvious that it has always 
seemed to me a paradox that it was not made long ago) we must 
absolutely separate the marine beds from the sub-aerial ones, put 
them into two entirely different columns and perhaps give them 
entirely different names. To apply the term Pliocene to the marine 
beds marked by the Norwich or the Weybourn Crag and to apply it 
also to the sub-aerial beds known as the Forest bed, is not an illumin- 
ating but a darkening process. These two sets of beds may have 
been contemporary but they have no other element in common, and 
it is utterly misleading to give them a common name because the 
marine and land debris are sometimes mixed as in the Norwich 
Crag just as Ammonites and Mammoths both may be mixed with 
striated boulders in the soft beds on the coast of Holderness. If we 
are to retain our present geological nomenclature for the pan-arctic 
region we must qualify each name by a distinctive epithet showing 
whether the bed we mean is in the marine or the sub-aerial series. 
Again, we continually read in geological books of unconform- 
ability, an excellent term expressing a very patent fact when we 
