NOMENCLATURE. 355 



the comprehension of this genus. Yet in their proper place 

 such changes may be indicated by "pro parte" or " char, muta- 

 tis" " excl. sp." and the like, useful qualifying statements, 

 but no part of the name. 



723. Exactness requires that when a group is changed from 

 a higher to a lower rank, or the opposite, the name of the 

 author who made the change should be quoted. 1 He alone is 

 responsible for it. But this rule has only recently been strictly 

 observed. 



724. In transferring a species from one genus to another, its 

 specific name must be preserved (with alteration of the gender, 

 if need be) , unless there is cogent reason to the contrary. It 

 must necessarily be changed when there is alread}' in that genus 

 a species of the same name ; and then synonymous names of 

 the transferred species have their claim in order of date. But 

 whatever name is first employed under the accepted genus, being 

 unobjectionable, should hold, even against an older unobjection- 

 able one coming from a wrong genus. This is an application 

 of the stringent rule that no needless names should be created.* 



1 Thus, Potentilla Canadensis, L., var. simplex, Torr. $ Gray, and not of 

 Michaux, for it is the species P. simplex, Michx. Geum, subgen. Styliput 

 Torr. $ Gray, not of Raf., for it is the genus Stylipus of Rafinesque, who 

 neither made the subgenus nor approved it. So, also, for the genus Labur- 

 num we write "Laburnum, Griseb. ; " for even if it exactly corresponded with 

 Cytisus sect. Laburnum of DeCandolle, the latter is not a group of equiva- 

 lent rank. 



But, as to genera and subgenera, this precision should not be insisted on 

 for times quite anterior to the recognition of such rules and of their need. 

 Spergularia began with Persoon as a subgenus in the year 1805, and this 

 date has been assigned to the genus, although it was taken up as such only 

 in 1819 by Presl and in 1824 by Bartling. 



2 Thus, hi the case of an older specific name being known, as that of 

 Chilopsis saligna, Don, recognized as Bignonia linearis, Cav., though Don ought 

 to have adopted the latter trivial name, yet as he did not (and the rule was 

 not then really in force as now), there was no need for the introduction 

 of a third name, Chilopsis linearis, DC. " So, again, an Indian Grass was 

 first named and described by Willdenow as Coix arundinacea, then named 

 by Roxburgh as Coix barbata, and entered in Sprengel's Systema with 

 Willdenow's character as Coix Kcenigii. All these names were defective 

 as referring to a wrong genus. Brown corrected the error by creating the 

 new genus Chionachne, and selected Roxburgh's specific name as the one 

 most generally known and the least liable to misinterpretation ; and Brown's 

 Chionachne barbata is therefore the first correct name ; for which Thwaites 

 afterwards substituted Chionachne Kcenigii, an entirely new and useless name, 

 which falls by the law of priority. It should be well borne in mind that 

 every new name coined for an old plant, without affording any aid to 

 science, is only an additional impediment." Bentham (Notes on Euphorbi- 

 aceae, in Jour. Linn. Society, xvii. 197, 198, November, 1878). The following 



