Febkuaey 27, 1903.] 



SCIENCE. 



351 



priority is rendered as effective with genera 

 as with species. 



ilany systematists have been content to 

 follow in a general way the varying nomen- 

 clatures of their predecessors, while others 

 who have appreciated the importance of uni- 

 form procedure have experimented with what 

 has been called the method of residues or 

 elimination, under which a generic name is 

 inherited by the last species left in the genus 

 after all possible segregations have been made. 

 This plan is defective in theory, very difficult 

 of application, and does not bring about uni- 

 formity in practice, because different system- 

 atists commonly differ as to which species 

 were rightly removed from the genus, and 

 consequently as to which in reality remained 

 to the last. Those who look upon stability 

 as the prime requisite of a system of formal 

 nomenclature are accordingly beginning to 

 abandon elimination in favor of the selection 

 of types by a definite method of priority, but 

 progress in this desirable direction is greatly 

 retarded by the fact that the rule which recog- 

 nizes 1753 as the beginning of binomial no- 

 menclature would have the unforeseen and 

 verj- undesirable result of associating many 

 old and well known generic names with spe- 

 cies for which they are not currently used, 

 that is, if it were not possible to find a means 

 of avoiding the difficulty. 



It seems certain that the consistent appli- 

 cation of any method will result in many 

 changes of names, since even in instances 

 where genera were established for single spe- 

 cies their names have frequently been slipped 

 along to groups of plants quite unknown to 

 the original authors. Rather than run the 

 risk of having to use old names in new and 

 unexpected places, some would give over the 

 attempt at securing stability. But to those 

 who perceive that taxonomic study is largely 

 a waste of time unless it can be carried on 

 under rules which guarantee uniform nomen- 

 clatorial results, no changes essential to the 

 application of such an improved method will 

 seem intolerable or ridiculous, though to make 

 unnecessary changes, even to carry into ef- 

 fect a good rule, would be foolish. Because 

 the guinea-pig would become Mus and the 



giraffe Cervus is not a reason why we should 

 not, in general, treat the first species as the 

 type of its genus; it is simply a reason why 

 we should find, if possible, a means by which 

 an undesirable incident may be avoided with- 

 out losing the important advantage of a 

 method which all can apply with uniform re- 

 sults. The plan of treating the generic names 

 adopted from pre-binomial writers as a special 

 case should not be opposed even as an excep- 

 tion to the general rule, since with these we 

 are not dealing with the normal method of 

 establishing genera, but are attempting to 

 arrange as smooth a connection as possible 

 between two periods of botanical history. It 

 is true that we are not following the intent 

 of eighteenth-century authors, since we now 

 think of generic names as attached to species 

 rather than to definitions or concepts, but 

 this should not make us unwilling to preserve 

 as many of the older names as possible, nor 

 careless in applying them as nearly as possible 

 in accordance with historical usage. 



Many of the older generic names which 

 would be transferred by taking either the first 

 or the last Linnsean species as type may be 

 kept in their customary places by selecting 

 as types species having such names as offl- 

 cinalis, utilis, communis, vulgaris, verus, 

 typicus or others indicative of botanical prom- 

 inence or popular interest. A rule containing 

 a list of such names would facilitate the selec- 

 tion of types and would be open to no charge 

 of indefiniteness. 



Another practical suggestion is that instead 

 of taking as types the first species placed by 

 Linnaeus under names adopted from pre-bi- 

 nomial writers, we take the species under 

 which Linnaeus gives the oldest citation under 

 the same generic name. This would place the 

 question of types on a definite basis of chron- 

 ology, and opens no doors to individual dif- 

 ferences of opinion. It would require con- 

 siderable bibliographic labor to locate the 

 oldest citation under some of the larger 

 genera, though this task is much more simple 

 and direct than the method of elimination. 

 The utility of such a rule for the purpose for 

 which it was intended will depend, however, 

 on whether Linnaeus followed a method of 



