nvrnoDUCTioN'. i' 



long. In this way you may find a great many of 

 the common forms and easily identify them *' by 

 the book." 



In making your beginning in these studies, take 

 the easiest first ; those that are commonest and have 

 easily distinguished marks. From the more easy pro- 

 ceed step by step to the more difficult. Do not spend 

 unnecessary care and labor in trying to make out 

 difficult cases. Put them aside for the present. 

 When you have had more practice it will be easier 

 for you. 



Again, you may presume a little on the good 

 nature and kindness of botanists, and especially of 

 Algologists, and send your difficult plants to them to 

 nanye for you. I have often done such sendee for 

 people. I thus try to repay the kindness and pa- 

 tience with which my footsteps were guided, when I 

 first set out in this path, by many far more distin- 

 guished botanists than I ever expect to be. I have 

 not a little indebtedness of this kind still unliqui- 

 dated, as I trust some of my readers will take the 

 liberty of finding out. 



Still another way to get help, is to get some 

 Algologist to spare . you out of his duplicates, by 

 exchange or purchase, some of the forms which you 

 are inquiring about, and thus have something authentic 



