A Project for Phytogeographic Nomenclature* 



By Ch. Flahault 



The role of botanic geography is relatively simple. Whatever 

 may be the extent of the territory considered, it proposes to es- 

 tablish statistics of the species which inhabit it, investigate their 

 origin, their migrations and their present and former distributions. 

 It is desirable that in immense countries like the United States of 

 North America, or Russia, on a desert island or in a province, 

 writers may be enabled to employ the same terms to designate the 

 various subdivisions of importance without being misunderstood* 

 Russian botanists divide all the European territory of the Czar's 

 empire into four regions ; a recent author recognized six in the 

 little island of Lesbos, the extent of which does not exceed several 

 square kilometers. 



While it is unfortunate in some respects that the meaning of a 

 word lacks precision, the subject itself explains enough of that 

 which is in question to cause no serious trouble in the variation of 

 the interpretations ; it is easy to return to the subject in question. 



This incoherency is the more to be regretted when it occurs in 

 works on botanic geography, Phytogeography becomes more 

 and more an exact science ; its principal aim is to make known the 

 multiple relations of vegetation to an environment however va- 

 ried. To express these relations it is important, then, that we 

 have an all-sufficient vocabulary on which those interested would 

 agree. This is an essential condition to all progress. Now, the 

 greatest disorder prevails in works on the subject of nomenclature 

 and on the subordination of geographic groups. Some use the 

 same term promiscuously for great extents of country and for ele- 

 vated mountain zones. For some, zones are tracts of land char- 

 acterized by forms of vegetation peculiar to plains, while regions are 

 applied to the mountains ; they say forest region, subalpine, al- 

 pine, nival regions, etc. For others, regions are territories in the 

 plains distinguished by peculiar vegetative and floral characters ; 



* Translation of a paper read by Professor Flahault at the International Botanical 

 — s, Paris, October, 1900. 



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