ORG A NIC E VOL UTION. 37 



speak, there have been made to maintain the 

 uniformity of type in the case of the arm, and 

 should we not expect that in other and similar 

 cases similar efforts should be made ? Yet we 

 repeatedly find that this is not the case. Even 

 in the whale, as- we have seen, the hind-limbs 

 are not apparent ; and it is impossible to see 

 in what respect the hind-limbs are of any less 

 ideal value than the fore-limbs, which, as we 

 have also seen, are so carefully preserved in 

 nearly all vertebrated animals except the snakes, 

 where again we meet in this particular with a 

 sudden and sublime indifference to the mainten- 

 ance of a typical structure. Now I say that if 

 the theory of ideal types is true, we have in these 

 facts evidence of the most unreasonable incon- 

 sistency ; for no explanation can be assigned 

 why so much care should have been taken to 

 maintain the type in some cases, while such 

 reckless indifference should have been displayed 



