219. THEORY OF THE SYSTEM. 



member of a series of individuals (. 218.), differ- 

 ing in nothing but their forms, may at the same 

 time be a member of another series of individuals, 

 differing only in the gradations of their colours, 

 See., the rest of the natural-historical properties 

 being supposed exactly to agree. 



Let A, B, C, D, . . . 



represent a Series of Individuals , in which the forms and the 

 colours are not yet determined, so that every one of those 

 letters signifies the aggregate of the remaining properties, 

 which are exactly the same in all of them. Hence in this 

 respect they differ from each other only by their succes- 

 sion, that is to say, by their not being one and the same 

 thing. Suppose, now, every individual to have the same 

 colour a, but different forms, without the latter of which 

 they would not be different individuals. According to our 

 supposition, these forms must be members of the same se- 

 ries, and may therefore be expressed by 



X, X + 1, X + 2, X + 3, 



where X may denote any fundamental form whatever. 

 The designation of the series of individuals, as above, only 

 including their forms and colours, will therefore be 

 I. A.a.X; B.a.(X+l); C.a.(X + 2); D.a.(X+3); ... 

 A fragment of another series of individuals may, under 

 the same restrictions as those mentioned above, be desig- 

 nated by 



. . . P, Q, R, S, . . . 



P, Q, R, &c. being similar aggregates of properties, as 

 A, B, C, &c. in the preceding series. Suppose the differ- 

 ence among the individuals to consist only in their colours, 

 which, according to the supposition, are members of one 

 series of colours. The colours of the individuals 



. . . b, c, d, e, . . . 



which represent members of a series of colours, may be 

 joined to a form X + n, common to them all, and to the 

 above mentioned aggregates, so that the entire designation 

 VOL. i. x 



