188 THE LAW. 



habit. Infinite variety of structure, infinite variety through 

 time, and infinite variety over space, seem leading charac- 

 teristics of the Creator's scheme ; and we err in our inter- 

 pretation when we try to establish for the .primeval world 

 a law that has ceased to operate in the new. It is true 

 that as we ascend in time, from higher to higher forms, the 

 areas of specific distribution seem to become more and more 

 circumscribed, and such a limitation would only accord with 

 the idea of increased diversity of species as dependent on 

 more localised varieties of food, climate, and other external 

 conditions ; but even on this point we must exercise great 

 care and discrimination. In the present continents we 

 trace, in some measure, the outline of former seas and 

 lands ; but more than two-thirds of the earth's crust are 

 covered by water, and hide from our research the continua- 

 tions of systems, a knowledge of whose extent is indispen- 

 sable to the solution of the problem. It is better, then, to 

 shape our inferences in accordance with what we know of 

 existing nature, and believe in variety and distribution of 

 species from the first, in various centres of creative mani- 

 festation, and in a process of local extinctions and crea- 

 tions which necessarily prevented universal uniformity of 

 Life during any of the geological epochs. 



[External Conditions never Uniform.] 



It has been argued, no doubt, that in the primeval epochs 

 our earth, in virtue of its internal heat, enjoyed a higher 

 and more uniform climate, and was consequently peopled 

 by a more uniform flora and fauna. This argument, like 

 many others of the earlier geologists, seems altogether with- 

 out foundation. Granting the existence of a higher internal 

 temperature in pre-vital times, and admitting its influence 



