OCTOBEB 29, 1900] 



SCIENCE 



597 



his approval. They relate not only to species- 

 less genera, but to genera based on a species, 

 or on a group of congeneric species, designated 

 only by a vernacular name, unaccompanied by 

 a diagnosis, or by an inadequate one. 



1. A generic name proposed without mention 

 of any described species is invalid unless it is 

 accompanied by a diagnosis of such a character 

 as to indicate that it is based on a previously 

 known species, or group of species, that can be 

 unequivocally identified as the basis of the diag- 

 nosis. Examples: Gavia J. R. Forster (1788), 

 based exclusively on the loons, a small group of 

 strictly congeneric species; Fregata and Picoides 

 Lac(?p6de (1799), based on single species obvi- 

 ously indicated by the diagnosis. 



2. A generic name, proposed with or without a 

 diagnosis, may be accepted if a genotype is 

 designated merely by a vernacular name of un- 

 equivocal significance. Examples: Plauius Briin- 

 nich (1771), based on an unmistakable diagnosis 

 of the great auk with the addition of tlie Danish 

 vernacular name of the species; Reguliis Cuvier 

 (1800), proposed, without diagnosis, for the king- 

 lets ("les Toitelets " = Motacilla regulus Linn., 

 as shown by Cuvier's previous (1798) use of 

 these names) . 



In cases like the one last mentioned, a vernac- 

 ular name is to be accepted as a genotype only 

 when the author thus employing it has used the 

 vernacular name accompanied by the equivalent 

 systematic name in a previously published work, 

 thus defining it beyond question. A vernacular 

 name is also (and not otherwise) available as a 

 genotype when accompanied by a reference to a 

 work or author where it has been defined. 



It is believed that these recommendations 

 can be accepted without risk of serious com- 

 plications. The first has long been a part of 

 the A. O. U. Code; the second is not formally 

 adopted as a rule, but is implied in the " re- 

 marks" under Canon X5XII. (p. Ixi) of the 

 Revised A. O. U. Code, which relates to 

 nomina nuda. The following has a direct 

 bearing upon this proposition : 



The names of genera and subgenera given with- 

 out diagnosis or any other indication of a type 

 than a vernacular name without a citation of its 

 previous use, as in Cuvier's " Tableau General des 

 Classes des Animaux," in the first volume of his 

 "Lecons d'Anatomie Compare" (and in •ther 

 similar cases), are tenable if the vernacular name 



is one that has been used and defined by a then- 

 current systematic name by the same author in a 

 previous work; the vernacuhir n:\me in such eases- 

 defines the type. J. A. Allen 

 Amehican MuSEU^t OF 

 Natub.\l History 



stable nomencl.\ture practicafxy 

 unattainable 

 To THE Editor of Science; I have read' 

 with much interest Mr. Jonathan Dwight's 

 article in a recent number of Science on 

 " The Burden of Nomenclature." While I am 

 in sympathy with this article, and with the 

 general tendency of modern systematic biolo- 

 gists to formulate rules and codes to govern 

 the application of generic and specific names, 

 I wish to emphasize the point that no matter 

 how perfect such a code may be we can not 

 hope that stability will be the immediate re- 

 sult. A very important factor in the applica- 

 tion of names is the study of the organisms 

 to which the names are applied. The perfect 

 code would indicate the application of the 

 names when the study of a group of organisms - 

 had been completed. When the study of all 

 organisms has been completed we may hope- 

 for a more or less stable nomenclature. Until 

 that time we must accept as inevitable a cer- 

 tain amount of change as groups are critically 

 studied. It is true that much of the change 

 during the present era is due to the use of 

 different codes, to misinterpretation of rules 

 and to what some are pleased to call the jug- 

 gling of names, that is, an attempt to fix names 

 without carefully studying the group con- 

 cerned. But aside from this there is what 

 we must accept as legitimate and inevitable 

 change due to increased knowledge of the 

 organisms and their nomenclatorial history. 

 It is not necessarily an adverse criticism of a 

 code that different editions of a list show 

 changes in nomenclature. In my own work 

 I have found that absolute stability of nomen- 

 clature is practically unattainable. Starting 

 with the traditional application of names in a 

 given group, investigation may show that 

 many of these names have been misapplied. 

 Two authors studying the same group at dif- 

 ferent times may apply the names in different 



