48 CODE OF NOMENCLATURE. 



be entirely rejected, or whether it may be considered available for a new and 

 valid genus. Usage seems strongly against the retention of such names ; 

 but a few writers have advocated their admissibility in some other class of 

 the Animal Kingdom, or even the admissibility of the same name in different 

 orders of the same class, as among insects. Inasmuch as a fixed rule is 

 desirable, and as practice and precept are both on the whole favorable to the 

 maxim quoted above, names in one department of Zoology being con- 

 tinually changed when found to be preoccupied in another department, 

 and as most previous codes explicitly state that a generic name to be 

 tenable must not be in double employ in the same kingdom, it seems to 

 your Committee that the formal adoption of the maxim, " Once a syno- 

 nym always a synonym," as regards generic names, must meet with general 

 approval. 



A 'synonym' is properly one of two or more different names for one and 

 the same thing. A ' homonym ' is one and the same name for two or more 

 different things. But in the usage of naturalists this distinction of meaning 

 is not generally recognized. Thus the examples about to be adduced in 

 illustration of the operation of Canon XXXIII. are homonyms, not syno- 

 nyms. It is therefore necessary to premise that your Committee includes 

 homonyms in the maxim just cited. 



The application of the maxim to specific and subspecific names has been 

 less generally admitted, but can be shown to rest on a sound principle, since 

 it aims at, and is calculated to promote, stability in names. The object of 

 the rule, in its present application, is to make the use of the specific name 

 altogether independent of the generic name ; to oblige authors to use always 

 the same specific name, even when they disagree as to the generic appellation. 

 In many cases, it is true, the revival of a specific name which has lapsed into 

 synonymy may lead to no confusion, but the cases where the reverse may 

 occur are far more frequent. To illustrate: Gmelin, in 1788, described a 

 Lark as Alauda rufa. Audubon, in 1843, also described a Lark as Alauda 

 rufa. In the mean time, however, the Alauda rufa of Gmelin has been 

 found to be a true Anthus, and being therefore transferred to that genus is 

 called Anthus rufus. Now as these birds belong to widely separated fami- 

 lies, it may be claimed that there is no possibility of confusing Audubon's 

 name with the Alauda rufa of Gmelin, and that therefore the name rufa of 

 Audubon is perfectly tenable. There are many parallel cases in zoological 

 literature, and the tendency is to recognize both names as valid. But the 

 case is not always so simple, being susceptible of several complications. 

 For instance, to continue the above illustration hypothetically, let us suppose 

 that, before the generic distinctness of the two species was discovered, the 

 name of the Audubonian Alauda rufa had been found to be preoccupied 

 and accordingly changed to rufescens, and that for many years the spe- 

 cies was known as Alauda rufescens. Finally the original Alauda rufa is 

 removed to Anthus^ and some writers restore to Audubon's species its origi- 



