'5 ( 6 ) 



kind of character we call generic, and the grouping it 

 indicates is a genus. 



Farther analysis brings to light characters of organ- 

 ism which are common to a still greater number of indi- 

 viduals ; this we call a family character. Those which 

 are common to still more numerous individuals are the 

 ordinal: they are usually found in parts of the structure 

 which have the closest connection with the whole life- 

 history of the being. Finally, the individuals compos- 

 ing many orders will be found identical in some impor- 

 tant character of the systems by which ordinary life is 

 maintained, as in the nervous and circulatory : the 

 divisions thus outlined are called classes. 



By this process of analysis we reach in our animal or 

 plant those peculiarities which are common to the whole 

 animal or vegetable kingdom, and then we have ex- 

 hausted the structure so completely that we have noth- 

 ing remaining to take into account beyond the cell- 

 structure or homogeneous protoplasm by which we 

 know that it is organic, and not a mineral. 



The history of the origin of a type, as species, genus, 

 order, etc., is simply the history of the origin of the 

 structure or structures which define those groups re- 

 spectively. It is nothing more nor less than this, 

 whether a man or an insect be the object of investi- 

 gation. 



EVIDENCES OF DERIVATION. 



a. Of Specific Characters. 



The evidences of derivation of species from species, 

 within the limits of the genus, are abundant and con- 

 clusive, In the first place, the rule which naturalists. 



