CLASSIFICATION. 315 



characters. Whatever resembles the genus Rose 

 more than it resembles any other genus, does so 

 because it possesses a greater number of the cha- 

 racters of that genus, than of the characters of any 

 other genus. Nor can there be the smallest difficulty 

 in representing, by an enumeration of characters, the 

 nature and degree of the resemblance which is strictly 

 sufficient to include any object in the class. There 

 are always some properties common to all things 

 which are included. Others there often are, to which 

 some things, which are nevertheless included, are 

 exceptions. But the objects which are exceptions to 

 one character are not exceptions to another : the 

 resemblance which fails in some particulars must be 

 made up for in others. The class, therefore, is con- 

 stituted by the possession of all the characters which 

 are universal, and most of those which admit of excep- 

 tions. If a plant had the ovules erect, the stigmata 

 divided, the albumen not obliterated, and was without 

 stipules, it probably would not be classed among the 

 Rosacese. But it may want any one, or more 

 than one of these characters, and not be excluded. 

 The ends of a scientific classification are better an- 

 swered by including it. Since it agrees so nearly, in 

 its known properties, with the sum of the characters 

 of the class, it is likely to resemble that class more 

 than any other in those of its properties which are still 

 undiscovered. 



Not only, therefore, are natural groups, no less 

 than any artificial classes, determined by characters; 

 they are constituted in contemplation of, and by 

 reason of, characters. But it is in contemplation not 

 of those characters only which are rigorously common 

 to all the objects included in the group, but of the 

 entire body of characters, all of which are found in 



