448 Transactions. 



and to make their recognition by subsequent workers a matter 

 of certainty. 



The binomial, or binary, system of botanical nomenclature, 

 which is the method now universally employed, was devised 

 by the celebrated Linnaeus, the bicentenary of whose birth has 

 this year been fittingly commemorated. Under it all those 

 species which agree in the possession of certain characters are 

 collected into a group called a genus, to which a substantive 

 name {Clematis, for instance) is applied. This name, which is 

 common to the whole of the species of the group, is called the 

 generic name. In addition to this, each one of the species is 

 distinguished by a separate adjectival name, called the specific 

 name ; for instance, Clematis indivisa. Thus every species has 

 two names — the first, or generic name, indicating the genus 

 to which the species belongs ; the second, or specific name, 

 pointing out the particular species. It is this combination of 

 the generic name with the specific epithet that constitutes 

 the great merit of the system invented by Linnaeus. Under it, 

 a means is provided by which every known species of plant 

 may have a technical name of its own, by which it can be known 

 to all botanists, and which at the same time is readily dis- 

 tinguishable from the name of any other plant. Its simplicity 

 and ease of application secured its immediate acceptance ; and 

 now, after the lapse of more than a hundred and fifty years 

 from its inception, it can be said that no serious attempt has 

 ever been made to depart from its leading principles. 



But, although no one proposes to dispense with the binomial 

 system, its practical working has, through a variety of causes, 

 become exceedingly difficult and troublesome. Instead of 

 stability of nomenclature, which is clearly the point to be aimed 

 at, we have arrived at a chaotic state of uncertainty, which has 

 a seriously deterrent effect on the study of systematic botany, 

 even if it is not fast bringing it into contempt. The reasons 

 for this regrettable state of affairs may be briefly particularised 

 as follows : — 



The botanical nomenclature of Linnaeus is now usually 

 considered to date from the publication of the first edition of 

 his " Species Plantarum " in 1753. For many years after this 

 date no difficulties of importance arose, although the absence of 

 any code of rules, or even of any well-defined understanding 

 as to modes of procedure, encouraged a laxity of practice sure 

 to create trouble in the future. 



Unfortunately, the idea of the inviolability of the specific 

 name, when once conferred, now considered to be a point of the 

 first importance, was of slow growth, so that eminent botanists, 

 on the most flimsy pretexts, did not hesitate to alter or even 



