PREFACE. 



THE science of botany is as eminently progressive as it is delightful and 

 ennobling. By recent discoveries it has been established on the basis of 

 inductive philosophy, and elevated almost to the rank of an exact science. 

 The theory of the lloral structure which refers each organ to the principle 

 of the leaf, now enters into almost every department of botany, and gives 

 a new aspect to the whole ; revealing more clearly than any other discov- 

 ery has ever done, the beauty and simplicity of the plan on which Creative 

 Power is exerted in the production of the countless forms of vegetable 

 existence. 



The present treatise contains, first, the Elements of Botany, according 

 to the latest authorities, written in the form of simple propositions, briefly 

 illustrated, and broken into short paragraphs, witli direct reference to the 

 convenience of the learner. Brief as it is, it is hoped that it will be found 

 to embody all the established principles of the science contained in former 

 school treatises, together with those newly discovered principles in Organ- 

 ography and Physiology, by which botany has been really enriched and 

 advanced.* 



The Flora is adapted particularly to that section of the United States 

 which lies north of the Capitol, that is, of the 39th parallel, including 

 essentially the States lying north of the Ohio river and Maryland.f It 

 comprehends all the PhaBnogamia, or flowering plants, with the Ferns, &c. 

 which have hitherto been discovered and described as indigenous in these 

 States, together with the naturalized exotics, and those which are more 

 generally cultivated either as useful or ornamental. The descriptions are 



* The student who aims at the highest attainments will hy no means rest satisfied with mere 

 outlines, such as our limits here admit of. It affords us pleasure to be able to recommend to all 

 such as would advance beyond first principles, the full and elaborate " Text Book " of Dr. Asa 

 Gray, an American work of the highest merit. 



1 With some exceptions, therefore, this Flora will answer for the adjacent States of Delaware, 

 Maryland, Virginia, Kentucky, Missouri, and the Canada*. 

 I* 



