No. 443.] 



MUTATION IN PLANTS. 



759 



niakin<r a denser more crowded rosette. The bases of the lam- 

 ina are almost cordate in some instances, and vary from oblong 

 ovate to ovate in outline, bein^- sparingly toothed. The plants 

 established in the soil in the open air did '!()t bloom until about 

 three weeks later than the parent and (E. rubrincrvis. No 

 noticeable departure from the characteristics assigned this form 

 by deVries was found. 



Seedlings of Uinothcra ntbrincnns were .seen to ha\c nar- 

 rower leaves throughout from the earliest stages. The rosettes 

 were very closely appressed to the soil, and in this stage the 

 margins of the long petiolate leaves were inrollcd, thus decreas- 



FiG. 6. — (Knoihera nanella. Adult rosette immediately preceding the formation of flowering 

 stem. Photograpli of living plant taken from directly above. (See Figs. 4 and 5.) 



ing their apparent width. Attention is to be called here to the 

 fact that comparisons of leaf forms in plants of this kind 

 are permissible only between organs on corresponding por- 

 tions of shoots. The laminae were more bluntly toothed than 

 those of the parent type, and the midribs occasionally bore a 

 tinge of red, while the entire shoot including the leaves of the 

 upper part of the stem showed a tendency to the formation of 

 anthocyan. The physical qualities of the leaf were strikingly 

 different from those of the parent, perhaps the most noticeable 

 feature being the great brittleness of the leaves and stems of 



