Jlie Scope of Dendrology. 431 



cation. I fail to see why the recognition of the difference be- 

 tween this important work of botanical taxonomy and the work 

 of systematic dendrology, serving two different purposes, con- 

 stitutes a hair-splitting between the "scientific" and the "prac- 

 tical." 



The expression "sister sciences of plant-geography and plant- 

 ecology," used in my paper was employed in the sense common 

 throughout English literature as a metaphorical equivalent for 

 "closely related." It indicates no exact family relationship. 



I do not believe Dr. Howe's remarks on plant-geography and 

 plant-ecology are abreast with the best later developments of 

 these subjects. As certain botanical journals have expressed an 

 intention to review this aspect of the paper discussion here is 

 unnecessary. 



Since its publication the paper has been read at my request by 

 several American botanists who tell me, without exception that 

 they not only find it clear but also do not get from it any such 

 impression as Dr. Howe appears to have been given. 



[The Editor has reluctantly given additional space to this 

 academic discussion in order to satisfy the author's sense of injury 

 by Dr. Howe's criticism. He must, however, protest that there is 

 still perversion in the definitions of the author, if the originators of 

 terms have any right to give them their meaning. 



The combination "biological dendrology" was for the first time 

 used by the Editor (so far as he knows) in making out a curricu- 

 lum for the forestry courses at Cornell University, and he knew 

 perfectly well what he meant, namely, not "the chief biologic char- 

 acteristics of important species" as the author proposes to define, 

 but a statement of the general biological laws to which trees of any 

 species are submitted in their development. On the other hand, it 

 was Dr. Gifford as Assistant Professor at Cornell, who invented 

 the term silvics, really as a mere shortening of the phrase "silvi- 

 cultural characteristics (i. e. part of the biology) of important 

 species," — precisely what the author proposes to make the defini- 

 tion of the broader subject of biological dendrology. 



As this definition suggests, silvics has, indeed, a practical object 

 — silviculture — in view. It does not, however, deal with problems 

 but with facts or observations. The problems begin only when 

 silviculture is to be practised, namely, how to apply these observa- 

 tions or facts. 



This much was needful to add in view of the committee work on 

 terminology by the Society of American Foresters.] 



