308 THE KINDS OF PLANTS 



plants are the results of evolution. Probably none of them 

 was created in the beginning as we now find it. 



Names of Species. — For more than one hundred and 

 fifty years (since Linnaeus published "Species Plantarum" in 

 1753), species have been known by two names, the generic 

 and the specific. The generic name is the name of the 

 genus or group to which the plant belongs: it corresponds 

 to a surname. The specific name belongs only to the par- 

 ticular species or kind: it corresponds to a given or Chris- 

 tian name. Both names are necessary, however, to desig- 

 nate the species. Thus Quercus is the generic name of 

 all the oaks. Quercus alba is one of the oaks (the white 

 oak), Q. virginiana (the live-oak) another. All maples be- 

 long to the genus Acer, and all elders to Sambucus. The 

 same specific name may be used in any genus, as the same 

 Christian name may be used in any family. Thus, there 

 is a Quercus nigra, Cyperus niger, Acer nigrum, the word 

 "niger" meaning black. 



By common consent, the oldest proper name of any 

 species must stand. If a species happens to have been 

 named and described twice, for example, the first name, if 

 in the proper genus, must hold; the later name becomes a 

 synonym. It sometimes happens that the same specific 

 name has been given to different plants of the same genus. 

 Of course this name can be allowed to stand for only one 

 species, and the other species must receive another name. 

 In order to avoid confusion of this and other kinds, it is 

 customary to write the author's name with the species- 

 name that he makes. Thus, if Gray describes a new 

 Anemone, his name is written after the plant-name: Ane- 

 mone cylindrica, Gray. The author's name thus becomes 

 an index to the history of the species-name. 



Plant-names are thrown into the forms of the Latin 

 language. When plants first were studied seriously, knowl- 

 edge was preserved in Latin, and Latin names were used 



