II. ON ORDERS, GENERA, AND SPECIES. 



1. What are ' Orders ' and ' Genera ' ? 



The Phtto-geographer finds grave difficulties placed 

 in his way, at the very outset of his investigations, by the 

 unsettled condition of systematic botany. He is frus- 

 trated in his comparisons by the uncertainties and ine- 

 qualities of the gi'oups, both ordinal and generic ; and he 

 is more especially impeded by the variable and discordant 

 views on species, which are so largely evinced in the 

 practices of technical botanists. For the purpose of 

 instituting comparisons between the vegetation of dif- 

 ferent places, of difi'erent countries, of different climates, 

 or of difi'erent eras, the Phyto-geographer resorts to the 

 arrangements of systematic botany, and to the descrip- 

 tive nomenclature of technical botanists. He must thus 

 deal with orders, genera, and species, or with similar 

 groupings of plants. What are these ? And what does 

 the use or application of such terms truly imply ? 



Botanical systematists in general cling tenaciously to 

 an idea, that orders and genera are things which have 

 some real existence, as groups in nature, designed and 

 intended by the Creator of Nature. Much apparent 

 ingenuity, too often having the reality of narrow pedan- 

 try, is exhibited in their laboured argumentation, as to 

 whether certain groups are ordinal or sectional, generic 



