f 



1917] 



STOBER— WINTER AND SUMMER LEAVES 



109 



leaves, but the conductive tissue is slightly better developed in 

 rosette than in stem leaves. 



On tfre whole, typical rosette leaves, where there is consider- 

 able shading and protection, are decidedly more mesophytic than 

 stem leaves. In winter leaves on stolons or runners there is a 

 tendency toward greater xerophytism than in stem leaves, but 

 on the whole the rosette leaves are more mesophytic in structure 

 than stem leaves. 





• 



f 



In conclusion, I desire to acknowledge my indebtedness to 

 Dr. H. C. Cowles and Dr. J. M. Coulter for helpful suggestions 

 and advice in this work. 



Allbright College 

 Myerstown, Pa. 



* 



