FAMILY CHARACTERISTICS 111 



plants that naturalists first perceived those gen- 

 eral traits of resemblance existing everywhere 

 among the members of natural families, in con- 

 sequence of which they added this kind of group 

 to the framework of their system. In France, 

 particularly, this method was pursued with suc- 

 cess ; and the improvements thus introduced by 

 the French botanists were so great, and rendered 

 their classification so superior to that of Linnae- 

 us, that the botanical systems in which Families 

 were introduced were called natural systems, in 

 contradistinction especially to the botanical clas- 

 sification of Linnaeus, which was founded upon 

 the organs of reproduction, and which received 

 thenceforth the name of the sexual system of 

 plants. The same method so successfully used 

 by botanists was soon introduced into Zoology 

 by the French naturalists of the beginning of 

 this century, Lamarck, Latreille, and Cuvier. 

 But, to this day, the limitation of Families among 

 animals has not reached the precision which it 

 has among plants, and I see no other reason for 

 the difference than the absence of a leading prin- 

 ciple to guide *us in Zoology. 



Families, as they exist in Nature, are based up- 

 on peculiarities of form as dependent upon struc- 

 ture ; but though a very large number of them 

 have been named and recorded, very few are char- 

 acterized with anything like scientific accuracy. 



