SYSTEMS OF CLASSIFICATION. 397 



hung up in the temple than thrown aside with ignominy. The 

 traveller, returning from his adventurous and perilous journey 

 of discover}', hangs up his knapsack with affection on the wall 

 of his study. But travellers must return to the fields if more is 

 to be done — and so must botanists; and each must have re- 

 course, again and again, to those helps which aided them so 

 well in their earliest journeys." 



In both artificial and natural systems, the lower divisions — 

 namely, the genera and species — are the same, the difference 

 between them consisting in the manner in which these divisions 

 are grouped into orders and classes. Thus in the Linnsean and 

 other artificial systems, one, or at most a few characters are 

 arbitrarily selected, and all the plants in the Vegetable King- 

 dom are distributed under classes and orders according to 

 the correspondence or difference of the several genera in such 

 respects, no regard being had to any other characters. The 

 plants in the classes and orders of an artificial system have, 

 therefore, no necessary agreement with one another, except in 

 the characters selected for convenience as the types of those 

 divisions respectively. Hence such a system may be compared 

 to a dictionary, in which words are arranged, for convenience of 

 reference, in an alphabetical order, adjacent words having no 

 necessary agreement with each other, except in commencing 

 with the same letter. In the Natural System, on the contrary, 

 all the characters of the genera are taken into consideration, 

 and these are grouped together into orders which correspond 

 in the greatest number of important characters ; and these orders 

 are again united, upon the same principles, into groups of a 

 higher order, namely, the classes. Wbile it must be evident, 

 therefore, that all the knowledge we necessarily gain by an 

 artificial system, is the name of an unknown plant ; on the other 

 hand, by the Natural System, we learn not only the name, but 

 also its relations to the plants by which it is surrounded, and 

 hence we get a clue to its structure, properties, and history. 

 Thus, supposing we find a plant, and wish to ascertain its name, 

 if we turn to the Linnsean System, and find that such a plant is 

 the Menyanthes trifoliata, this name is the whole amount of the 

 knowledge we have gained ; but by turning to the Natural 

 System instead, and finding that our plant belongs to the order 

 Gentianace(B, we ascertain at once from its affinities, that it 

 must have the tonic and other properties which are possessed 

 by the plants generally of that order, and, at the same time, 

 we also learn that it accords in its structure with the same 

 plants; and hence, by knowing the name of a plant by the 

 Natural System, we at once learn all that is most important in 

 its history. It is quite true that all the orders, as at present 

 constituted, are by no means so natural as that of the Gen- 

 tianaceae, but this arises from the present imperfection of our 



