INTRODUCTION 
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diagnoses, the generic names of the Species Plantarum are taken in conjunction with the corre- 
sponding generic descriptions of the Genera Plantarum (ed. 5) of Linnaeus, 1754: thus, it is really 
agreed to regard the date of publication of the latter work as identical with the date of publication 
of the former. 
Nomina conservanda 
However, to avoid disadvantageous changes in the nomenclature of genera by the strict 
application of the principle of priority in starting from the date of issue of the Species Plantarum 
( 1 753 ), certain generic names must be retained under all circumstances. The list of nomina 
conservanda appended to the International Rides includes the following British genera : — Selaginella , 
Suaeda, Spergidaria, Eranthis, Corydalis, Nasturtium, Capsella , Oxytropis, Villarsia , Calystegia, 
Mertensia , Wahlenbergia , Silybum, Taraxacum , Leersia, Hierochlo'e, Corynephorus, Cynodon , Glyceria , 
Luzula , Narthecium, Maianthemum , Romulea, Spiranthes, Listera, Neottia , and Liparis. 
Doubtful books 
Although the fixing of a date as the starting-point of nomenclature might be thought to be 
a matter of very definite application, yet, on closer inspection, it is found that this is not the case. 
It has been pointed out to us that Haller’s Enumeratio Plantarum Horti Regii et Agri 
Gottingensis, having been published in 1753, the names in this work have to be taken into 
account in nomenclature. This, however, is not the case. It is not 1753 which is the starting- 
point, but the publication of the Species Plantarum (1753). Now, the latter work was published 
in two volumes ; and we are informed that Haller’s work, although published after the first volume 
of the Species Plantarum , was issued before the publication of the second volume of Linnd’s great 
work. Haller’s book, therefore, is pre-Linnaean. 
There are, however, some other works with regard to which it is not quite so easy to 
decide whether or not the names they contain must or must not be considered in nomenclature. 
We refer to certain works which, though published after the Species Plantarum (1753), yet belong 
to the pre-Linnaean era in the sense that they use Tournefortian genera and not Linnaean 
genera, and in the sense that they do not adopt the binominal method of naming species. 
Examples of such works are: — Miller’s Abridgment of the Gardeners Dictionary ed. 4 (1754); 
Miller’s Gardener s Dictionary ed. 7 (1759); Hill’s British Herbal (1756); Hill’s Flora Britannica 
(1760); and Haller’s Historium Stirpium Indigenarum Helvetiae Inchoata (1768). 
Different botanists take different views as to the standing of these books in nomenclature. 
First, some botanists maintain that all the names which do not actually contravene the rules, 
in these books should be adopted ; and accordingly they cite from them certain generic names 
and also certain binominals, for it must be remembered that binominals existed to some extent 
before Linnaeus applied them universally. Secondly, some other botanists maintain that it is 
only the generic names in these books which need be taken into account in nomenclatorial 
matters, and that the binominals must be ignored. We ourselves take up a third position. We 
regard these books, for the reasons already given, as being pre-Linnaean in every respect except 
mere chronology, as being an overflow, as it were, from the pre-Linnaean era into the post- 
Linnaean era. Accordingly, we do not utilise any of the names in the books in question. We 
can appreciate the point of view of those botanists who use both the generic names and binominals 
in these books ; but it appears to us to be illogical to choose to utilise the generic names and 
reject the binominals. As there is such a divergence of opinion in the matter, it seems to us 
imperative that, at the next international botanical congress of botanists, to be held in London 
in 1915, some definite ruling on the matter should be given. As we ourselves have to make 
a decision before the meeting of this congress, we unhesitatingly choose the third of the above 
plans — the rejection of all the names in the books in question. We choose this plan, first, because 
it results in conserving many names established in botanical literature, whilst the adoption of 
either of the other two plans would result in undesirable confusion ; and secondly because the 
rejection of all the names of the books in question has been the practice of almost all 
responsible botanists during the whole of the nineteenth century, whilst very few (and these only 
quite recently) have adopted the names of the books to which we allude. It is, of course, 
because of this almost universal practice that the names in question have become established in 
botanical literature. 
