1C6 THE ARTIFICIAL SYSTEM. 



871. INTERMEDIATE GROUPS, formed on the same principles, are recognized as 

 Subgenera, Suborders or Tribes, and Subclasses or Cohorts, which will be further 

 noticed and described in another place.* 



872. METHODS OF CLASSIFICATION. Two independent and widely different 

 methods of classifying the genera have been generally approved, the Artificial Sys- 

 tem of LinnEeus, and the Natural System of Jussieu. The former is founded solely 

 on characters relating to the organs of fructification, leaving all other natural affini- 

 ties out of view. The latter, on the contrary,' takes for its basis all those natural 

 affinities and resemblances of plants whereby Nature herself has distinguished them 

 into groups and families. 



CHAPTER II. 



THE ARTIFICIAL SYSTEM. 



873. A SYSTEM OF CLASSIFICATION IS SAID TO BE ARTIFICIAL WHEN, disregard- 

 ing tlio real nature of the subjects classified, it rests merely on some obvious exter- 

 nal circumstance. As when the books of a library are arranged on shelves accord- 

 ing to their size, octavo, duodecimo, etc., or as when the words in a language are 

 arranged in dictionaries, alphabetically, forming thus class A, class B, etc. In either 

 case the books or the words constituting any group may be quite diverse in charac- 

 tor, having nothing in common except their octavo size or initial letter. The only 

 use of such an arrangement is convenience of reference. 



874. CARL VON LINNE (Linnaeus) of Sweden, born in 1707, everywhere honored 

 as the father of systematic and descriptive botany, was the author of that renowned 

 artificial system which bears his name. For well nigli a century it continued in al- 

 most universal use, and was regarded by his followers with far more respect than by 

 Linnseus himself, who designed it simply as an index or clue to the vegetable king- 

 dom. For ho says (Philosophia Botanica) " Methodi Naturalis fragmenta studiose 

 inquirenda sunt. Prirnum et ultimum hoc in Botanicis desideratum est." 



875. CONSIDERED AS A SYSTEM, the Linnsean arrangement totally fails to exhibit 

 those true relations and affinities of plants which render the knowledge of each kind 

 a guide to that of the others, and combine all into one consistent whole. It can not, 

 therefore, properly be regarded as a system. 



876. CONSIDERED AS AN INDEX or key to the vegetable kiugdom, it is by no 

 means reliable, for the stamens and styles often vary numerically in the same 

 plant ; and secondly, the species of the same genus often vary in these respects, thus 

 obliging us to violate even specific affinities ; and again, when the stamens or pistils 

 are accidentally marred, or lost, or immature, the index must also foil of its purpose. 

 For these reasons this arrangement has fallen into disuse, having been superseded 

 by the Natural System, and by other arrangements better adapted to the present 

 advanced state of the science. Yet being intimately connected with the history of 

 i >otany, and having largely contributed to its early progress, its outlines at least de- 

 mand a record in our pages. 



877. THE LINNSEAN SYSTEM proposes to arrange all the known 

 genera of plants under twenty-four classes, each based on some special 

 character derived from the essential floral organs, as follows : 



