106 STUDY OF NATURAL HISTORY. 



But the question resolves itself into this, Are there 

 any fixed and universal laws by which the variations 

 of the forms of nature are regulated ? If this question 

 can be answered in the affirmative ; if all these 

 variations can be traced to certain primary types, 

 following each other in one constant and unchanging 

 series, we have the most conclusive evidence that 

 human research can elicit. It will be our especial 

 object, therefore, in the subsequent volumes of this 

 work, to demonstrate the truth of this proposition, 

 appealing for its stability to those facts with which 

 we first commence the fabric of the science, and 

 which, coming within the range of ordinary observ- 

 ation, it will be in the pow r er of every one to verify 

 or disprove. 



