HYBRID PLUMS. 



213 



some difference of opinion, I am aware, as to the wisdom of making botan- 

 ical names for such cases as these, but the writer is one of those persons who 

 believe that it is nothing against a variety or a species that we should know 

 its origin. The fallacy of requiring a man to be ignorant about any par- 

 ticular points regarding his material in order that- he may call it a species has 

 often been pointed out. 



Much interest has been aroused recently by the experimental work of 

 De Vries. His work is somewhat in the same line as that which is here 

 reviewed; and those who justify him in calling his groups species will doubt- 

 less be content to speak of Prunus hortulana robusta, P. triflora rustica, etc. 

 Those who stick to the strictly old-fashioned and conservative notion of 

 species naming may justly take exception to the practice here illustrated. 



