1919] 



ARIETIES AND COMBINATIONS 47 



under art. 48: '* The subgenus Alfrcdia Less, of the genus Rhaponticum 

 keeps its name when placed in the genus Carduus: Carduus sect. Alfrcdia 

 Benth. & Hook, f." 



I am therefore inclined to maintain in every case the oldest name regard- 

 less of change of grade or so-called rank. The name of the author, however, 

 should be changed with a change in the grade, if the nature of the grade is 

 clearly defined in both instances; if the original author failed to designate 

 the grade, the fixation of the grade is an emendation and the name of the 

 orighial author should be kept. If a combination is used as a trinomial the 

 author of the original combination should be quoted regardless of any 

 later change of grade. 



To designate a certain subdivision of a species it is only necessary to add 

 the name of this subdivision to the binomial, omitting the names of any 

 higher grades which may have been placed between this particular subdivi- 

 sion and the specific name. A combination of three names should always 

 be sufficient to designate any group below the species. This, of course, 

 d(x*s not apply to exact taxonomic work where names and combinations 

 should be cited exactly as published by their author. 



As to precise citation, I want to draw attention to the fact, that in most 

 publications names i)ublished as synonyms are cited as if published as valid 

 names; it seems advisable to add in such cases always after the citation the 

 words ** as a synonym " or " pro synon." and in exact citation also the 

 name of the group under which the name in question is placed as a synonym. 

 Likewise should the fact that a name has been published without descri]>tion 

 or reference to a previous descrii)tion, and therefore not valid, be brought 

 out by the addition of the words ** nomen " or " nomen nudum," or of 

 " nomen seminudum," if an insufficient refe;rence, perhaps a reference to an 

 illustration without description, is given. 



\Yhen it seems desirable to abbreviate citations as much as possible, one 



may restrict the author citation in cases where two authors (the author of 

 the manuscript name and the publishing author) are given to the name of 

 the publishing author; this is particularly important in names cited as 

 ** IL>rt."; e. g. Gesnera Donklarii Ilort. apud Hook, should be abbreviated 

 G, Donklarii Hook. The citation " Ilort." alone is almost meaningless, as 

 it not infrequently happens that the same name has been used for different 

 plants in different gardens and as this citation docs not give the slightest 

 hint when and where such a name may have started. The author who first 

 publishes such a name with a description makes the name valid and is really 

 the author of the name from a nomenclatorial point of view. 



At this institution wc have to deal to a great extent with forms of culti- 

 vated plants and their nomenclature presents some additional diflficulties 

 which cannot be entirely solved with the help of the International Rules of 

 botanical nomenclature. We have therefore to take into consideration the 

 rules accepted by the International Congress of Horticulture at Brussels in 

 1910. These rules were originally published in Bull. Soc. Bot. Belg. xlvii. 

 419-424, preceded by a detailed preliminary^ report (pp. 363-419); an Eng- 



