Likeness, Filiation, Heredity. 99 



that a species was a collection of organic individuals 

 more or less resembling one another, in their external 

 aspect, or internal structure; productive in their 

 unions among themselves, so that they perpetuate 

 the same collection in nature, by generating other 

 individuals of the same kind; and one of the conse- 

 quences thereof is, that originally all can have de- 

 scended from one primitive pair, identical in kind 

 with themselves. 



109. In this definition you have divers elements. 

 There is that of likeness, whereby they Likeness 

 resemble one another more or less. Filiation, 

 There is that of filiation, whereby the Heredity. 

 members of the group, or the posterity spoken of as 

 continuing the same collection in nature, are the off- 

 spring of their predecessors in the same class. 

 There is heredity, whereby the group perpetuates cer- 

 tain qualities, having received them by the process 

 of generation, that is to say, by proceeding as 

 living beings from living beings in the same likeness 

 of nature. 



no. Such classes as these are what the term, 

 species, strictly taken, is meant to designate. Now 

 does scientific induction show that such classes 

 really exist in nature? It does. Nearly one hun- 

 dred and fifty thousand are enumerated in the ani- 

 mal world alone. The individuals composing any 

 such class may differ in form, shape, size, features; 

 but they remain identical in a certain natural ca- 

 pacity for uniting among themselves, and perpetuat- 



