I have been guided by the hints given by the learned 

 Dr. J. E. Smith, in his excellent " Introduction to Bo- 

 tany." The classes Dodecandria and Polyadelphia are 

 entirely omitted, and their genera inserted in their pro- 

 per places in the other classes. Asariim next to ^ris- 

 tolockia, in Gynandria. Bejaria^ Portulacca, Talinum, 

 CalUgonum, and Hypericum, in Polyandria. Hudso- 

 nia next to Helianthemum, with which it is closely 

 related in the same class, Decumaria, Lythrum, Cu- 

 phea, and Agrimoniay in Icosandria. Halesia near 

 Sty rax, in Monadelphia. Euphorbia in Didinia, where 

 it forms, with its other genera, a natural as well as ar- 

 tificial order. The nineteenth class, Diclinia, contains 

 the natural families of Tricoccse or Euphorbia, Amen-^ 

 taceae, and Coniferse. The other genera of the classes 

 Monoecia, Dioecia, and Polygamia, having been re- 

 ferred to their proper classes. The genus Diotis more 

 properly belongs to Tetrandria, but had been omitted in 

 that class. Najas and Valisneria are genera of an 

 order of this class, to which probably might be added 

 all the Aroideee. How far these alterations may meet 

 the approbation of those best qualified to judge, I have 

 yet to learn, but I am strongly persuaded they will 

 facilitate the study of this lovely science to the young 

 beginner. 



In the last class, Cryptogamia, I have gone no fiirther 

 than the family of the Filices, according to the forma- 

 tion of the plan of this work, which only included 

 plants which either are, or can be cultivated. The other 

 orders, Musciy Algae, and Fungi, will form a distinct 

 work from the present, and may appear at some future 



