No. 436.] LOCALIZED STAGES IN PLANTS. 



247 



tion is a simpler and therefore more reversionary character than 

 any found either in the seedling- or the early spring growth. 

 This may be compared to what is seen in simpler species as 

 figured by Lubbock, P. repetans L. and others as mentioned 

 above in which the first nepionic leaf is simple although dentate 

 in outline. Potent ilia t ride n lata may therefore be considered 

 accelerated in development in that it has skipped the simple leaf 

 stage in early development. It is an important fact that in the 

 ontogeny of the individual the simplest stage found occurs not 

 in the young but as a definite feature of localized senescence. 



Geum virginianum L. Figs. 10, 11. 



Of this species seedlings were not obtained, but the early 

 leaves in other species as figured by Lubbock ( Geum free wont ii 

 Hort. and G. eoceincum Sibth. and Sin. Vol. 1, p. 486, fig. 313) 

 are orbicular with varied dentations, more or less deeply cut. 



In early spring growth of adults the first leaves are of this 

 same character. In the specimen, Fig. 10, the first three leaves 



had dropped off before it was drawn. The fourth leaf has the 

 orbicular form like the seedlings as noted but begins to show a 

 three-lobed character by the deeper notches on the sides. The 

 fifth is deeply cut and the trilobate character much stronger. 

 The next leaf number 6 is not only trilobate but has begun to 



