CLASSIFICA TION. 63 



I have taken the common Oxcdis ccr'niut as an 

 example of a flowering plant in general. Now, there 

 are several kinds of Osdalis, so like 0. ccr mia in the 

 structure of the flower and fruit, as well as the leaf 

 (this being mostly trifoliate, i.e. of three leaflets), that 

 botanists agree to call them all by the same name, 

 Ox alls ; but they differ in having their corollas red, 

 purple, white, or streaked, as well as yellow. Again, 

 in some the peduncle or main flower-stalk carries only 

 one flower, as 0. gla'hra with a violet-purple corolla. 



Again, like 0. ccr'nua, a species may have an umbel 

 of flowers, but of a flesh-colour instead of yellow, such 

 as 0. liv'ida. 



I have mentioned only one or two points of 

 difference, but there are others. If tliey amount to, 

 say, five or six, then botanists maintain that any two 

 with so many differences should be regarded as distinct 

 species. With less than that, they should be recognized 

 as varieties only. Since, however, all the important 

 points in the structure of the flowers and fruits is the 

 same, they all constitute one Genus. Hence is the 

 necessity of giving two names to every plant, the 

 " generic," as Ox'alis, and the '' specific," as cer'nua. 

 Botanists have now named upwards of a hundred 

 species of the genus Ox'alis in South Africa alone, while 

 there are other species elsewhere. In England there 

 is one with white flowers called the wood-sorrel. 



The student must learn the true meaning of 



