10 NATURAL HISTORY. 



that a strictly ' natural ' classification embodies the know- 

 ledge of the time as to the lines of descent of animals 

 from primordial types, it would seem difficult to overrate 

 the value and importance of the study of classification. 



Finally, we should have to study each species of animal 

 from still another point of view, which, however, is 

 indissolubly connected with the study of its palseonto- 

 logical relations and its systematic position. We should 

 have, namely, to inquire into its mode of origin and its 

 history as a species. This constitutes what is known as the 

 science of EVOLUTION. 



The above seven heads would embrace the principal 

 sorts of knowledge which the naturalist would find it 

 needful to obtain with regard to any particular species of 

 animal, if he wished to write a complete history of it. 

 Natural history as a whole is, therefore, only the aggregate 

 of our knowledge, under all these seven heads, of all 

 known animals, living and extinct. Perhaps, if our means 

 of investigation were thereto adapted, we should have, 

 further, to study each animal as regards its Psychology, 

 or from the side of its mental activity, and also as 

 regards its Teleology, or the end for which it exists, and 

 the purposes which it subserves in the general economy 

 of nature. At present, however, we have no adequate 

 means for the study of the psychology of animals; and 

 an inquiry into the teleology of animals is necessarily 

 ultra-scientific. It follows from what has been just 

 remarked, that the departments of knowledge requisite 

 to give us a complete acquaintance with any one 

 animal are also the great departments of the science 

 of zoology. Hence, modern natural history consists 



