NOKTH -CAROLINA GEOLOGICAL SURVEY. 



leading facts respecting the characteristics of the period in 

 which the respective nations lived. 



So, also, the characteristics of the fossils furnish at least a 

 clue to the features of the epoch during which they lived. 

 To determine these features, demands an intimate knowledge 

 of the present ; for, we are under the necessity of comparing 

 the past with the present. The present is the standard, and 

 no comparison can be made of any value which neglects the 

 present. We find in the present certain structures and forms 

 which we know have certain relations to climate, or to the 

 conditions in which they exist. If, then, similar structures or 

 forms are found attached to an extinct being of any epoch, it 

 is a fair inference that that structure or form bore a similar 

 relation to the external conditions which surrounded it. Its 

 full description, then, would be a memoir of the animal, its 

 habits would be indicated, its relation to surrounding circum- 

 stances would be known ; many inferences would follow from 

 each, some would bear only upon its instincts, its food, its 

 means of defence from the medium in which it lived, etc. 



If, for example, an oval shaped bag filled with coloring 

 matter, in connection with a fossil known as the Belemnite, it 

 would be inferred that this bag contained a fluid designed to 

 conceal it from its enemies ; that it would deeply discolor the 

 water into which it was cast, and thereby, under its cloud of 

 dye-stuff, make its escape. Such a phenomenon is familiar 

 now to the sailor. The cuttle-fish is thus supplied with dye- 

 stuff, and he employs it for escaping from a pursuing enemy ; 

 and as this is so, so it is inferred, the animal did which was 

 supplied w T ith a similar apparatus in the period of the Lias and 

 Chalk. 



We might go on and note hundreds of analogous examples, 

 but one must suffice. This view is borne out by one great 

 and leading fact, that all extinct animals are constructed upon 

 one of the four leading types which now prevail. Of the mil- 

 lions of individual fossils which have been seen, not one is 

 known which does not belong to, and may be referred with 

 certainty, to one of the great leading types of the present. It 

 is* the plan then, which really tells all this, or makes it possi- 



