E. V. Wulff —204— Historical Plant Geography 



only for designating genetic elements, others that it be applied only to 

 geographical elements. The advocates of the latter alternative ad- 

 vance as grounds the fact that the initiator of this term, Christ, ap- 

 plied it only in a geographical sense, and that only later, beginning 

 with Engler, was it used in a genetic sense. The advocates of the first 

 alternative maintain that Christ used this term in both a geographical 

 and genetic sense. Nevertheless, most investigators have been inclined 

 to believe that the geographical factor is of primary importance and 

 that the term "element" should be applied to it. 



This discussion led to a number of proposals of different names for 

 the various categories of elements enumerated above. Thus, Reichert 

 (1921) proposed to designate as floral elements only genetic elements, 

 and to call geographical elements "components". For migration ele- 

 ments he gave the term "migrants", for those migrants that pene- 

 trated into a given flora during the same historical period the term 

 "historical migrants", and for those that arrived from the same general 

 region and by the same route "locative migrants " ("lokativer Migrant "). 



Wangerin (1932), in a paper devoted especially to this topic, main- 

 tains that the term "element", if used at all, should be used in its 

 geographical sense, but, in view of the confusion that has arisen in 

 connection with the various ways in which the term is applied, he 

 proposes that it be discarded altogether and replaced by an entirely 

 different term, "Arealtype", that would leave no doubt as to its 

 geographical application. In this connection it may be pointed out 

 that this last term is by no means new, for Hooker (1855) in his 

 "Flora Indica" grouped species into types (European, Siberian, Ma- 

 layan, etc.), having in view the same concept as Wangerin. 



It seems to us that burdening science with superfluous terminology 

 is not at all desirable; in most cases it does not eliminate confusion but 

 rather contributes to it. The term "component", for instance, is al- 

 ready used in biocoenology and in an entirely different sense. It is 

 much simpler to preserve the term "element" and to add a descriptive 

 adjective {e.g., genetic, geographical, migration, historical, ecological) 

 in order to make clear the precise meaning in which the term is used. 

 This seems all the more advisable, since the new terms proposed do not 

 by far cover all the meanings of the term "element". Thus, the fol- 

 lowing terms have become widely adopted: relic element, endemic ele- 

 ment, Tertiary element, Quaternary element, etc. In order in such 

 cases to avoid the use of the term "element", one would have to de- 

 vise a whole string of new terms which would never be widely ac- 

 cepted. 



Of considerably greater significance are the proposals made by Eio 

 (1931), not so much as regards the concept "element", by which he 

 understands "ecological element", but as regards a more profound 

 analysis of floras, chiefly with respect to ecology and phytocoenology. 

 He points out that, in case the flora of a given territory does not spread 

 beyond the boundaries of a definite floral region, this flora will possess 

 only one basic element ("element base") — he has in mind a relic, not a 

 migration, flora. If, however, the territory under investigation em- 

 braces two or more floral regions, its flora wiU comprise an equal 

 number of basic elements. 



