4 INTRODUCTION. . 6- 



ral-historical properties, because herein consists the only 

 object of its consideration. Yet this is not on account of 

 the difficulties, which attend the explanation of the mode 

 in which natural productions have been formed, but be- 

 cause it acknowledges principles, which entirely exclude all 

 explanations of this kind. Thus the principles of Natural 

 History fix the extent and the limits of that science ; 

 limits which it cannot transgress without inconvenience. 

 Yet it is not thereby too much confined, since whatever 

 may thus be excluded, does not belong to Natural His- 

 tory itself, but to other sciences. Every addition from 

 these would only serve to contaminate the fundamental 

 principles of Natural History. It is a matter of the highest 

 importance to keep the sciences perfectly distinct from each 

 other, and strictly within their respective limits, in order to 

 become acquainted with their stronger and their weaker 

 parts, and to assist wherever it should be necessary ; but 

 the philosopher must not possess them separately. The 

 sciences might be compared to working tools set in dif- 

 ferent handles, and subservient to different purposes. The 

 intelligent naturalist is like an able artist, who knows how 

 to employ them conformably to his design. 



. 6. INDIVIDUALS. 



A natural production, in as far as it is a single 

 body, and, as such, by itself fit to be an object of 

 natural-historical consideration, is termed a Natu- 

 ral+Historical Individual* 



Natural productions, which are not individuals, or whose 

 individuals are no more recognisable, may, nevertheless, 

 be objects of examination, according to the principles of 

 Natural History. The idea of individuality implies unity 

 of form ; and by this an individual becomes an independ- 

 ent whole, whose natural-historical consideration does not 

 presuppose the existence of, or at least not the con- 

 nexion with, another individual. In Natural History, 



