690 



may have unconsciously influenced the author of the * Manual,' when 

 adopting into that useful work the newly coined generic name from 

 the conceited Parlatore. 



The subdivision of one large genus into two or more genera, how- 

 ever, may be excusable and allowable, when founded upon clear and 

 decided characters. Yet can it seldom be necessary, or even desira- 

 ble, thus to multiply synonyms; since a subgeneric section would 

 usually answer the scientific purposes fully as well, — though not 

 ministering so satisfactorily to the personal vanity of the name- 

 changer. Thus, the separation of Luzula from Juncus, of Armeria 

 from Statice, being favoured by considerable diversity of general habit, 

 as well as by fair enough technical characters, it was soon acquiesced 

 in by botanists; as also that of Linaria from Antirrhinum, of Pelargo- 

 nium from Geranium, made on conspicuous floral differences, although 

 not accompanied with equally decided distinctions of habit. On the 

 contrary, the separation of Eleocharis from Scirpus is bad ; because 

 the technical distinction, derived from a trifling peculiarity in the 

 style, makes a most unnatural subdivision of the genus; half the 

 species which correspond with Eleocharis in general habit, being still 

 left in the genus Scirpus. 



Some botanists will change also the specific name, together with 

 the generic name of a plant, and thus interpose an additional obstacle 

 in the way of identifying the synonyms as those of one single species. 

 This course is necessary, indeed, when a species is removed from one 

 genus into another, and becomes associated under the same generic 

 name with another species already bearing the same specific name ; 

 otherwise we should have two species with the same names, both 

 generic and specific. And when two or more genera are united, the 

 one discarded generic name is occasionally taken up for a specific 

 name ; as in the instance of Potentilla Tormentilla. 



We have premised these remarks on name-changing, as excep- 

 tional cases where the recognized rule of priority will not enable 

 botanists to select the right name of a species. By itself, that rule 

 is simply a matter of date or time, and its application is usually easy 

 and certain. The true difliculties of nomenclature arise from the 

 vexed questions touching the limits between species and varieties, 

 and from diversities of opinion respecting the characters which are to 

 be deemed sufficient or insuflicient for the establishment of genera. 

 These are not matters of date. They are points to be decided by the 

 acquired knowledge and sound judgment of botanists ; and as indi- 

 viduals differ most widely from each other in such mental qualities, 



