24 ECONOMIC BOTANY OF ALABAAIA 



almost under our eyes. This is easily demonstrated in the case of 

 cultivated ])lants, and it is undoubtedly taking place in wild plants, 

 (as shown by fossil remains), though much more slowly. 



\\ hen what was universally regarded as a single species with 

 pretty definite characters is divided into two or more, the change 

 is often resented by botanists who are not taxonomists, and still 

 more by persons who are not botanists but have to deal with the 

 plants in question in one way or another (e.g., lumbermen and 

 farmers), for it requires readjusting ideas and learning new names. 

 But it would be absurd to say that no more changes of this sort 

 should be tolerated hereafter, for we cannot afford to stop in our 

 tracks and shut our eyes to new discoveries. At the same time the 

 process of splitting species seems to have already been carried 

 beyond all reasonable limits in some groups of plants by specialists 

 who make that their chief occupation, and would be out of employ- 

 ment and soon forgotten if they did not occasionally break into 

 print that way. Fortunately — one might say — the number of per- 

 sons thus engaged is smaller in proportion to the total number of 

 botanists now than it was ageneration or two ago,* and the splitting 

 process has not been carried as far with trees and shrubs — except 

 in a few genera — as it has with ferns and grasses, or with birds 

 and mammals in the animal kingdom. 



A certain amount of this sort of work is necessary, or at 

 least desirable ; and newly discovered differences which may seem 

 at first to be slight and unimportant may turn out to be very sig- 

 nificant. To take a hypothetical example, it might be found that 

 all the specimens of a certain shrub east of a certain meridian 

 yielded poisonous honey, while those farther west, separated by a 

 few hundred miles, i^erhaps, and distinguishable at sight only by 

 blooming a couple of weeks earlier, or having a few more stamens 

 in the flowers, might have no such properties. Or we may take 

 some more specific cases. A century ago it was commonly believed 

 that our ])ines which yield tur])entine in large quantities were all 

 one species, and they are still so treated by some geologists and 

 soil surveyors ; and our cypresses likewise. But it is now well 

 known that the slash pine prefers wetter soils than the long-leaf, 

 and has flifferent l)ark, leaves and cones, produces seed oftener, 



*See A. S. Hitchcock, vScience 11.67:431-432. April 27, 1928. 



