CONCERNING NOMENCLATURE. 297 



While the generic name of a plant must necessarily 

 be changed when it is transferred to another genus, 

 there is no need of a change in the specific name unless 

 the new genus should already possess a species of the 

 same name. There cannot, of course, be two species of 

 the same name in any genus. It has frequently hap- 

 pened, however, that botanists in transferring species 

 have assumed the right to make new specific names. 

 These names some botanists would discard for the oldest 

 specific names without regard to the circumstances 

 under which they were given, but there is a large body 

 of students who look upon a plant as not named until 

 it -is placed in the right genus and hold that the first 

 correct combination of generic and specific names is the 

 proper name for the plant no matter by what other 

 specific names it has been known. The name of the 

 botanist who made the correct combination is then 

 written after it. This is essentially the system that has 

 been adopted in the nomenclature of the Check-List 

 following the Keys to the Species in this volume. 



When a plant originally described in one genus is 

 transferred to another, it is the practice of many bota- 

 ists to place in parenthesis after the specific name, the 

 authority for that name, and to follow it with the name 

 of the botanist who made the correct combination. 

 Thus in the case of the rusty woodsia which is now 

 cited as Woodsia Ihensis (L.) R. Br., we are to under- 

 stand that Linnaeus gave the specific name Ilvensis to 

 the plant, and that Robert Brown was the first to make 

 the correct combination of generic and specific names. 



The fern collector, interested in learning the names of 

 his plants, pays little attention to the Orders. He is 

 concerned with genera and species. Almost at once he 



