(4) 



again. In annuals such spurious species will only 

 reappear occasionally. 



Questionable types can be investigated only by 

 cultivation. Up to this time California does not 

 possess a botanical garden or experimental grounds 

 where such questions could be definitely settled. 

 Therefore the solution of many problems has been 

 left entirely to enthusiasts who utilize their leisure 

 hours in the cultivation of doubtful species, fre- 

 quently under great difficulties. 



Owing to these circumstances, there is scarcely 

 an author writing on our Flora who has not been 

 compelled to frequently change or correct his pre- 

 vious views, and I hope the present author will be 

 excused if in future times investigations shall lead 

 him to add to, or to retract, some of his state- 

 ments. 



H. H. BEHR, M. D. 



