THE FIFTY YEARS' LIMIT IN NOMENCLATURE. 91 



own ; and if this were carried on to any considerable extent, the 

 result may be imagined. 



On this point we are entirely in accord with M. Briquet, who 

 writes : " Malgre la sympathie que nous eprouvons pour nos savants 

 confreres du Musee de Berlin, nous voudrions voir leurs regies 

 passees au crible d'une discussion generale apres quelques annees 

 d'experience, et cela dans I'interet de la nomenclature elle-meme. 

 Si chaque musee adopte nn code particulier, on pent prevoir, etant 

 donne les divergences qui existent actaellement, que Ton ne tendra 

 pas a se rapprocher de ruuiformite desiree." 



It is not, however, the rules in general, but one of them in par- 

 ticular, to which the recent action of Prof. Engler has attracted our 

 attention. The rule in question has been criticized unfavourably 

 by M. Briquet, by Dr. Britton, and by ourselves, and it might have 

 been hoped that this similar expression of opinion on the part of 

 those who are not otherwise entirely in accord would have suggested 

 the desirability of its reconsideration. Such, however, has nob been 

 the case. 



It may be worth while to quote the rule and the objections that 

 have been made concerning it : — 



" 2. Ein Gattungsname wird aber fallen gelassen, wenn derselbe 

 wahrend 50 Jahre von dem Datum seiner Aufstellung an gerechnet, 

 nicht in allgemeinen Gebrauch gewesen ist. Wurde derselbe jedoch 

 als eine Folge der Beachtung der ' Lois de la nomenclature vom 

 Jahre 1868 ' in der Bearbeitung von Monographieen oder in den 

 grosseren Florenwerken wieder hervorgeholt, so soil er bei uns in 

 Geltung bleiben."! 



M. Briquet's comment runs thus ; it will be observed that he 

 considers the rule was directed primarily against another German 

 botanist, and as he was in correspondence with Prof. Engler on the 

 subject of the rules, he is likely to be well informed : — 



" 2. Get article constitue la grande innovation des botanistes 

 berlinois. La limite prescriptive de cinquante ans a pour but 

 d'eliminer de la nomenclature une serie de vieux vocables genSriques 

 remis en vigueur recemment par M. 0. Kuntze et divers auteurs 

 americains. Mais le principe de la prescription cinquantenaire est 



entoure de restrictions qui en rendent I'application delicate 



Nous considererions comme dangereux I'adoption dejinitive saus 

 experience prealable du principe de la prescription, tel qu'il est 

 enonce par les botanistes berlinois." | 



Dr. Britton wrote : — " The application of the ideas embodied in 

 this paragraph would lead to great uncertainty in very many cases, 

 and we do not believe that the Berlin botanists will long maintain 

 them. How they can consistently decide on what is ' general use ' 



* Bull, de I'Herb. Boissier, 1897, 774. 



t i' 2. — The name of a genus is, however, allowed to lapse if it has not been 

 in general use during fifty years, counted from the date of its establishment. 

 If the name has, however, been revived in monographs or large floras as a result 

 of following the ' Laws of Nomenclature of the Year 1868,' that name is to hold 

 good." 



\ Bull, de I'Herb. Boissier, Sept. 1897, 775. 



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