26 ECONOMIC BOTANY OF ALABAMA 



When a genus or species is divided of course a new name has 

 to be given to one of the components. The name of a plant may 

 also he changed without a change in classification, on account of a 

 new inter])retation of an old description, or something of the sort, 

 and this has caused a great deal of annoyance in recent years. 

 Half a century ago plant names were determined largely by usage 

 and authority, like ordinary language ; but under this system the 

 original describer of a plant had no assurance that the name he 

 gave it would not be displaced by a later one coined by some more 

 or less eminent "authority." About forty years ago a movement 

 began to establish nomenclature on a permanent basis, by giving 

 the earliest generic or specific name precedence over all others, 

 unless there was some very good reason for doing otherwise, such 

 as the name itself being preoccupied. That resulted in the imme- 

 diate discarding of innumerable names which had long been in use ; 

 but the reformers tried to assure the multitude of objectors that 

 everything would be straightened out in a few years, and the 

 revised names would soon become as familiar as the displaced ones. 

 This hope has not been fully realized, however, on account of the 

 frequent discovery of old descriptions in obscure places, correc- 

 tions of disputed dates of publication, differences of opinion in 

 interpreting inadequate descriptions, etc., besides the changes 

 directly and indirectly due to changes of classification. The rules 

 have been revised at several international botanical congresses, but 

 complete agreement has not yet been reached. For example, one 

 faction seeks to retain by s])ecial enactment a long list of generic 

 names which were in use practically throughout the 19th century, 

 while others want to follow rigid rules and make no exceptions. 



As far as nomenclature itself is concerned, this catalogue fol- 

 lows pretty closely the recent works of Dr. John K. Small, who 

 has written several floras of the southeastern states and parts 

 thereof. But a more conservative attitude toward genera and 

 species necessitates the use of names different from those in his 

 books in some cases. However, where different names are used in 

 different books, both are given here, to make it as convenient as 

 possible for the reader. In dealing with trees the 1933 edition of 

 Sargent's Manual of the Trees of North America and the 1927 

 edition of Sudworth's Check List of the Forest Trees of the 

 United States have been followed as far as possible. 



