UNITY OF SYSTEM. 59 



pared to the Old World, its present Fauna being more analogous to the 

 later Tertiary of Europe. 



This inferiority of America did not occur till the more recent geolo- 

 gical time, for in the Paloeozoic Age, to the close of the Coal Period, 

 it was as brilliant and profuse in its life as any other part of the world. 

 In the above epoch, the globe was in an important sense not individualized 

 in its climates, or its distribution of life, and only partially in its seas. 



The whole of known American species of animals of the Permian, 

 Triassic, Furassic, Cretaceous, and Tertiary Periods, is about two thousand, 

 while in Britain and Europe, a territory even smaller, there are more 

 than twenty thousand species. The Eastern world, that is, Europe, Asia, 

 and Africa combined, has taken the lead in Animal life ever since Paloeozoic 

 times. In the Eeptilian Age, Europe and Asia had species by thousands, 

 while America was almost untenanted. 



As between the hot equator and the frigid zone, tribes have now their 

 limits in geographical distribution, so in geological times, between the 

 warm Silurian Age and the cool present one, there was a localization of 

 groups in time, a chronological distribution, an increase and period of 

 maximum at different epochs along the ages. A few genera reach from 

 the very dawn of life to the existing period; they are continuous lines, 

 binding creation in one. 



The Articulate tribe appeared first in their lower and aquatic forms 

 — Crustacea and Worms, and did not attain their perfection until the 

 close of the creation. They increased in number and variety of structure 

 as the land was raised from the sea, and in proportion to the increase 

 of diversity in climate, in soil, and in plants. 



When the epoch of man approached, the land was enlarged, the 

 mountains were raised, and consequently the valleys and the rivers were 

 formed; the climates were more varied; each region had its peculiar 

 vegetation and animals, and these became most numerous in kinds, and 

 acquired their greatest variety and beauty. When man was placed on 

 the earth, the day or epoch of rest ensued. The creation was then 

 completed, and no new kind of creature afterwards came into existence. 



The summary of the preceding notes may be comprised in the following 

 words: — The most perfect and characteristic form of each inferior group 

 did not, in order of time, immediately precede the period of each superior 

 group, but passed away previous to that epoch, and there were more or less 

 complete and long intervals of cessation of existence on the earth between the 

 epochs. Each group of creatures in proportion as its species have a more 

 developed organization, recedes further in afl&nity from all the other groups, 

 whether superior or inferior to it; and, in process of time, is reduced 

 wholly or partially to what it has in common with all other groups, or 



