THE PLANT WORI.D 



107 



tinct lobes, the middle one of which is the most striking feature of the 

 leaves at this stage of development (figs. E and F). Figure F shows the 

 two leaves of different ages upon the short rhizome, which now begins to 

 differentiate. The plant represented in figure G is a still more advanced 

 juvenile form. This form of juvenile leaf is frequently arrested, and pro- 

 tects the flower bud which subsequently grows up within its rolled edges. 

 The appearance of this leaf is followed by a more evolved form (fig. H), 

 in most cases associated with the formation of flowers and fruit. This 



form of leaf may be said to represent the first adult stage of develop- 

 ment of the bloodroot and it is followed by other leaves which are larger, 

 more prominently veined, and which show seven well-marked lobes separ- 

 ated from each other by rounded sinuses. Coincident with this enlarge- 

 ment of the leaves, the rhizome, which arises from the fusiform hypo- 

 cotyl, grows in length and thickness, until, in the older plants, it may 

 be several inches long and fully one-half to three-quarters of an inch thick. 

 The amount of orange-colored latex also increases with the age of the 

 rootstock. Elsewhere the write r * has presented measurements of these 



♦Harshbkkger, The Limits of Variation in Plants, Proc. Acad. Nat. Sci. Phila., 1901, pp. 306-308. 



