46 Our Native Ferns. 



found their way into accepted text-books of botany.* Specific 

 names frequently indicate something regarding habit or mode of 

 growth or may indicate the locality in which the organism was 

 first discovered. A few take their name from their discoverer, in 

 which case the name is Latinized and takes a genitive ending. 

 The derivation of the specific names of our native species will be 

 found in the glossary. 



87. The advantage of this binary nomenclature is at once evi- 

 dent when we consider the immense number of ferns alone, to say 

 nothing of the remainder of the vegetable world and the hosts of 

 the animal creation. By this means organisms of complex struc- 

 ture can be definitely characterized with comparatively few words 

 and the scientific name once established remains the same among 

 scientists of all nations and languages. 



88. There are, however, liabilities to error and confusion in 

 the Linnsean system of nomenclature, as various authors have 

 often assigned the same name to several species. For example, 

 the name Cheilanthes vestita was given by Brackenridge to Eaton's 

 C. graciUima. Hooker assigned the same name (in part) to Nutt- 

 all's C. lanuginosa, while Swartz assigned the same to the fern de- 

 scribed in this volume under the name of C. vestita. It becomes 

 necessary, therefore, in referring to a species to indicate the author 

 of the specific name usually, if written, by an abbreviation. 



8g. ^yaarrymy. — It may also be remarked in this connection 

 that different authors have described the same fern under widely 

 different generic and specific names. For example, the delicate 

 Woodsia Ilvensis of Brown was described as Acrostichuni Uvense 

 by Linnaeus, Polypodium Uvense by Swartz, Nephrodium rufidu- 

 lutn by Michaux, Aspidium rufidulum by Willdenow and Woodsia 

 rufidula by Beck. Many other species have been as variously 

 classified. From the confusion of the past we are rapidly emerg- 

 ing and our nomenclature is coming to be established on a per- 

 manent and scientific basis. 



90. Species. — Goethe tells us that nature knows only individ- 

 uals, and that species exist only in the school-books. From this 

 extreme there has been every grade of opinion respecting species 

 to the direct opposite which regards species as invariable, 

 actual existences, types originally ordained and summoned to ex- 

 istence by the Creator. Linnaeus, for example, defined species in 

 these words : " Species tot sunt diversce, quot diversas formas ab 



*Clstqpteris for Cystoptens is an example. 



