THE GEKANItJM FAMILY. 206 



particulars from Tropseolum and Impatiens, both of which, In 

 recognition of their wide departure from more primitive forms, 

 are now placed in separate families. The study of such a series 

 of forms is in the -highest degree instructive, presenting as it 

 does very important evidence regarding the descent of these 

 peculiarly modified genera. 



SPECIAL STUDIES. 



I. Varieties of cultivated " geraniums," and how they 

 are produced. 



II. Epidermal appendages of different genera and their 

 function. 



III. Relation of the genera Geranium and Tropeeolum. 



IV. Mechanical arrangements for the dissemination of 



seeds. 

 V. Limits of the Geraniaceas and their affinities. 



