TH E A M ER I CA N BOTA N I S'J" 55 



tliciii. I 'mil real relatiun^hips were recognized, therefore, 

 plants had to he classified as edible, poisonous, niedicin.al and 

 the like. A somewhat better classification wa> that which di- 

 vided the plants into trees, shrubs, herbs and lianas or woody 

 \ ines. Indeed, this classification is still used by nurserymen 

 and seednien and serves their purpose fairly well. It does 

 not, however, always bring like species together and is there- 

 fore anything but scientific. 



Ikit even when the plants were [)roperly catalogued tliere 

 still existed the difficulty of finding the name of an unknown 

 l)lant. This difficulty was also solved in a measure by Lin- 

 naeus, who devised a sort of botanical index or "key" by 

 which a given species might be traced through the maze of 

 [)lants. By dividing tlie plants into groups according to the 

 number of stamens tliey produced, and then subdividing these 

 groups according to the number of carpels possessed, he made 

 divisions small enough to make it reasonably certain that one 

 might soon locate his species. That this was an artificial 

 system was recognized by everybody, but until the affinities 

 of plants were understood it served the purpose. The keys 

 that now are a part of every popular guide to the plants are 

 often highly artifici.'d, tlie sole object of course being to pro- 

 duce the name of the plant without undue labor or loss of time. 



The object of scientific classification however, it to place 

 like species together in a natural grouping and the keys in 

 technical manuals are nearly always based on this arrange- 

 ment. In some cases both natural and artificial keys stand 

 side by side. The beginner finds the artificial keys easier at 

 first because they sieze upon the most obvious characters for 

 distinguishing tlie species, but the natural keys give more 

 fundamental differences. 



Of the botanical manuals most commonly used, Britton's 



