THE VEGETABLE AND ANIMAL KINGDOMS. 121 



is nevertheless connected in character with the briefer process 

 by which an individual being is evoked from a simple germ. 

 What mystery is there here and how shall I proceed to enun- 

 ciate the conception which I have ventured to form of what 

 may prove to be its proper solution ! It is an idea by no 

 means calculated to impress by its greatness, or to puzzle by 

 its profoundness. It is as much marked by simplicity as 

 perhaps any other of those which have explained the great 

 secrets of nature. But here, again, it may be said, lies one 

 of its strongest claims to our faith. 



My proposition is that the several series of animated beings, 

 from the simplest and oldest up to the highest and most 

 recent, are the results, first, of an inherent impulse in the 

 forms of life to advance, in definite times, by generation, 

 through grades of organization terminating in the highest 

 dicotyledons and vertebrata, these grades being few in num- 

 ber, and generally marked by intervals of organic character 

 which we find to be a practical difficulty in ascertaining 

 affinities ; second, of another inherent impulse connected with 

 the vital forces, tending, in the course of generations, to modify 

 organic structures in accordance with external circumstances, 

 as food, the nature of the habitat, and the meteoric agencies, 

 these being the " adaptations" of the natural theologian. We 

 may contemplate these phenomena as ordained to take place 

 in every situation, and at every time, where and when the 

 requisite materials and conditions are presented in other 

 orbs as well as in this in any geographical area of this 

 globe which may at any time arise observing only the 

 variations due to difference of materials and of conditions. 

 The nucleated vesicle is the fundamental form of all or- 

 ganization, the meeting-point between the inorganic and 

 the organic the end of the mineral and beginning of the 

 vegetable and animal kingdoms, which thence start in dif- 

 ferent directions, but in a general parallelism and analogy. 

 This nucleated vesicle is itself a type of mature and inde- 

 pendent being, as well as the starting point of the foetal 

 progress of every higher individual in creation, both animal 



