THE DOCTRINE OF FINAL CAUSES. 509 



lead to the notion of a different sort of animal com- 

 position. Molluscous animals had been placed too 

 high in the zoological scale ; but if they are only 

 the embryos of its lower stages, if they are only 

 beings in which far fewer organs come into play, it 

 does not follow that the organs are destitute of the 

 relations which the power of successive generations 

 may demand. The organ A will be in an unusual 

 relation with the organ C, if B has not been pro- 

 duced; if a stoppage of the developement has 

 fallen upon this latter organ, and has thus pre- 

 vented its production. And thus," he says, "we 

 see how we may have different arrangements, and 

 divers constructions as they appear to the eye." 



It seems to me that such a concession as this 

 entirely destroys the theory which it attempts to 

 defend ; for what arrangement does the principle of 

 unity of composition exclude, if it admits unusual, 

 that is, various arrangements of some organs, ac- 

 companied by the total absence of others ? Or how 

 does this differ from Cuvier's mode of stating the 

 conclusion, except in the introduction of certain 

 arbitrary hypotheses of developement and stoppage. 

 "I reduce the facts," Cuvier says, "to their true 

 expression, by saying that cephalopods have several 

 organs which are common to them and vertebrates, 

 and which discharge the same offices; but that 

 these organs are in them differently distributed, and 

 often constructed in a different manner ; and they 

 are accompanied by several other organs which 



