THE ANNULOSE TYPE. 607 



originally simple and not segmented animals, especially the fact that there 

 is originally one pronephric duct or primitive kidney." 



Nevertheless there survives a leaning towards the notion of a 

 segmental origin of the Vertebrata. But the repetitions of organs 

 named in support of this notion have, I think, no more relation 

 to the genesis of the vertebrate type than the multiplication of 

 vertebrae in a snake has relation to the genesis of the vertebral 

 column. 



