368 CONSTRUCTION OF 



perfect. This kind of character is, however, 

 admirable for the illustration of any difficult 

 natural order, Mr. Gavvler's elucidations of 

 the Eiisata, Sword-leaved plants, Annals of 

 Bofanif, v.l. 219, and Curt, Mag. afford 

 excellent specimens of it, serving as a store of 

 facts and observations for following systema- 

 tical writers. 



Specific characters should be constructed 

 on sniiiiar principles to the generic ones, as 

 far as regards certainty, clearness and con- 

 ciseness. The genus being first well defined, 

 we are to seek for characters, not mentioned 

 among the generic marks, for distinguishing 

 the species. A specific difiference for a soli- 

 tary species of any genus, is therefore an ab- 

 surdity. Linnaeus at first intended his spe- 

 cific definitions should be used as names ; but 

 the invention of trivial names happily set 

 aside this inconvenient scheme. On this ac- 

 count however he limited each to twelve 

 words, a rule to which ail philosophical na- 

 turahsts have adhered, except in cases of 

 great necessity. Nor is the admission of one 

 or two words beyond the allotted number re- 

 prehensible, provided the whole sentence be 



