[35] DIRECTIONS FOE COLLECTING PLANTS KNOWLTON. 



The temporary labels should be kept constantly with their plants. 

 Final labels should not be written until the plants have been mounted. 

 To economize time these should consist as far as possible of printed 

 blanks. In mounting, care must be taken to leave a sufidciently large 

 space at the lower right-hand corner for the label, and if, as often hap- 

 pens, more than one plant requiring separate labels go on the same 

 sheet, room for all the labels must be provided for prior to mounting. 

 The following forms of labels have been used in the herbarium of the 

 National Museum : 



Ex Hekb. U. S. National Museum. 



Hab. 



Leg. 



FLORA OF ARIZONA. 

 Collected, in the San Francisco Mountain. 



No. 



Collected by F. H. Knowlton. 



1889. 



