3G2 PRINCIPLES OK CLASSIFICATION. 



cause of the strong family likeness which pervades the whole, and 

 of the transitions between them. In the larger of these suborders, 

 or the proper Rose family, Ave recognize three trihes : one repre- 

 sented by the Rose genus itself; one by the Bramble genus, with 

 the Strawberry, Cinquefoil, Avens, &c. ; and the third by Spiraea 

 and its near relations. And, again, the second and larger of these 

 embraces genera which are ditferent enough to be ranked under 

 several subtribes. 



706. Upon the same principles, groups may be interposed between 

 the orders and the classes, of which the highest kind will take the 

 name of Subclasses. And even above classes we have the most 

 comprehensive division of all plants into a higher and a lower grade 

 or Series (98) ; which brings us up to the vegetable Kingdom, 

 one of the three great departments of Nature. 



707. To exhibit the whole sequence or stages of natural-history 

 classification, so that the student may see the relative rank of groups, 

 designated by the terms which have now been explained, they are 

 here presented, arranged in a descending series, beginning with the 

 primary division of natural objects into kingdoms, and indicating by 

 small capitals those of fundamental importance and universal use in 

 classification. 



Kingdoms, 

 Scries, 



Classes, 



Subclasses, 



Orders or Families, 

 Suborders, 

 Tribes, 



Subtribes, 

 Genera, 



Subgenera, 

 Species, 



Varieties, 



Individuals. 



708. Characters. An enumeration of the distinguishing marks, or 

 points of difference between one class or order, &c. and the others, 

 is termed its character. Characters accordingly properly embrace 

 only those points which are common to all plants of the group, but 

 'not to the other groups of the same rank. The characters of 

 classes, &c. are restricted to those general peculiarities of structure 

 upon which these great groups are established : the ordinal charac- 

 ter recites the particulars in which the plants it comprises differ 



