240 PHILOSOPHICAL NOTES ON BOTANICAL SUBJECTS. 



Similarly, if we find carpels changing into toothed leaves, we 

 have no choice but to conclude that the teeth are the homologues 

 of ovules. 



:N'one of these parts need be histologically identical, or have 

 the same function. To consider them homologues it is enough 

 that they should occupy the same position, and be sometimes 

 convertible one into the other. 



