CLASSIFICATION BY SERIES. 448 



the only sciences in which this general principle has hitherto heensuc- 

 cesslully adopted in the construction of a nomenclature. 



Besides the advantage Avhich this principle ot'nomenclature possesses, 

 in giving to tlje names of species the greatest quantity of" independent 

 significance wliiih the circumstances of the case admit of, it answers 

 the further end of innnensely economizing the use of names, and pre- 

 venting an otherwise intolerable hiu-den upon the memory. When the 

 naiDes of species become extremely numerous, some artifice (as Mr. 

 W'hewell* observes) becomes absolutely necessary to make it possible 

 to recollect or apply them. " The known species of plants, for ex- 

 ample, were ten thousand in the time of Linnaeus, and are now prob- 

 ably sixty thousand. It would be useless to endeavor to frame and 

 employ separate names for each of these species. The division of the 

 objects into a subordinated system of classification enables us to intro- 

 duce a Nomenclature which docs not require this enormous immherof 

 names. Each of the genera has its name, and the species are marked 

 by the addition of some epithet to the name of the genus. In this 

 manner about seventeen hundred generic names, with a moderate 

 number of specific names, were found by Linnasus sufticient to desig- 

 nate with precision all the species of vegetables known at his time." 

 And though the number of generic names has since greatly increased, 

 it has not increased in anything like the proportion of the multiplica- 

 tion of known species. 



CHAPTER VIII. 



OF CLASSIFICATION BY SERIE.S. 



§ 1. Thus far, we have considered the principles of scientific classi- 

 fication so far only as relates to the formation of natural groups; and 

 at this point most, of those who have attempted a theory of natural ar- 

 rauffement, including, among the rest, Mr. Whewcll, have stopped. 

 There remains, however, another and a not less important pt)rtion of 

 the thef)rv, which has not yet, so far as I am aware, been systemati* 

 cally treated of by any winter except M. Comte. This is, the aiTange- 

 ment of the natural gi-oups into a natural series. 



The end of C'lassification, as an instrument for the investigation of 

 nature, is (as before stated) to make us think of those objects together, 

 which ha.ve the greatest number of important common properties ; and 

 which therefore we have oftenest occasion, in the course of our induc- 

 tions, fiir taking into joint consideration. Our ideas of objects are thus 

 brought into the order most conducive to the successful prosecution of 

 inductive inquiries generally. But when the purpose is to facilitate 

 some particular inductive in(|uiry, more is recpiired. To be instru- 

 mental to that purpose, the classification must bring those objects to- 

 gether, the simultaneous contemplation of which is likely to throw 

 most light upon the particular subject. That subject being the laws 



♦ Philosophy of the Inductive Sciences, i., p. 489. 



