180 



THE GENESIS OF SPECIES. 



[CHAP. 



been termed by Mr. Eay Lankester " homogeny ; " 1 and 

 (2) a relationship induced, not derived such as exists 

 between parts closely similar in relative position, but with 



PART OF THE SKELETON OF THE LOBSTER. 



no genetic affinity, or only a remote one, as the homolo- 

 gical relation between the chambers of the heart of a bat 

 and those of a bird, or the similar teeth of the thylacine 



1 See Ann. and Mag. of Nat. Hist., July 1870. 



