346 PHYTOGRAPHY. 



And as the number of known species increased, so did the 

 length of the phrases which were needed for their discrimina- 

 tion. These " differentiae," thus used as specific names (the 

 nomina specified of Linnaeus) , became extremely cumbrous. It 

 was about in the middle of his career that Linnaeus suggested 

 what he called trivial names (nomina trivialia) for the specific 

 name, consisting of a single word ; and in the Species Plan- 

 tarum, in 1753, he carried this idea into full effect in Botany. 

 The step was a simple one, but most important ; and Linnaeus 

 himself, who generally did not underrate his services to science, 

 seems hardly to have appreciated its practical value. 1 



704. The Binomial Nomenclature in Natural History, thus 

 established, first separated the name of a plant or of an animal 

 from its diagnosis, descriptive phrase, or character, and reduced 

 the appellation to two words, the first that of its genus, the sec- 

 ond that of its species. The generic name very nearly answers to 

 the surname of a person, as Brown or Jones; the specific answers 

 to the baptismal name, as John or James. Thus, Quercus alba is 

 the botanical appellation of the "White Oak ; Quercus being that 

 of the genus, and alba (white) that of a particular species ; while 

 the Red Oak is named Quercus rubra ; the Scarlet Oak, Quercus 

 coccinea; the Live Oak, Quercus virens ; the Bur Oak, Quercus 

 macrocarpa : Magnolia grandiflora is Large-flowered Magnolia ; 

 M. macrophylla, Long-leaved Magnolia, and so on. The name of 

 the genus is a substantive, or at least is a word taken as a substan- 

 tive. That of a species is mostly an adjective adjunct, always 

 following the generic name and in the same gender. 2 This com- 

 bination of generic and specific name is the name of the plant. 8 



705. By this system, not only is the name of the plant reduced 

 to two words, but a comparatively moderate number of words 

 serves for the complete designation of more than 120,000 plants, 4 



1 Moreover, he may be said to have adopted rather than originated the 

 idea ; for single-worded specific names were used half a century previous 

 by Bachmann, alias Rivinus. 



2 It is to be noted that the classical Latin names of trees are all feminine, 

 therefore Quercus alba, Pinus rigida, &c. 



8 The name of a subgenus is sometimes written in between the two parts 

 of the plant's name, as Prunus (Padus) Virginiana. This is the name of the 

 plant and something more. In addition to the name of the species, that of 

 the variety or even subvariety is sometimes added. 



* Alphonse DeCandolle several years ago estimated the known species of 

 Flowering Plants at between 100,000 and 120,000. The larger number may 

 perhaps include the higher orders of the Flowerless series. In the present 

 state of our knowledge of the lower orders of Cryptogams, no close estimate 

 can be well formed of the actual number of species. 



