PREFACE. 



Vll 



A. Corolla polypetalous (79-319). 



B. Corolla gamopetalons (monopetalous) . .(320-536). 

 0. Incomplete flowers , (537-Y73). 



D. Diclinous flowers (774-903). 



E. Composites (904-1000). 



In the divisions, " Corolla polypetalous" and " Incom- 

 plete flowers," plants witli polyandrous flowers will be 

 generally missed, as they were done with in §§ 6-76; 

 but when they are met with again, it is for good reasons. 



"Whenever a genus is represented by one species only 

 (in our Flora), the specific name is given — ^for example, 

 Symplocos tinctoi'ia; and whenever the generic name alone 

 — ^for example, Lysimachia — ^is found, it is to be under- 

 stood that the genus is represented by more species than 

 one. When species of a genus differ so widely as to be 

 equivalent to sub-genera, they will be met with in the same 

 or in separate paragraphs, as StyUsma eooloulsides, Choisy, 

 and StyUsma JPichermgii, Gray, or Phala/ris d/rundi- 

 nacea, and Phalaris Cana/riensis, L. 



Sometimes a genus (or a species) will be met with twice, 

 or oftener, in distant divisions. Thus, we have Penihorurrv 

 sedoides in the division " Corolla polypetalous," as well as 

 in that of the "Incomplete flowers ;" for the flowers of this 

 species have sometimes a corolla, and oftener none. Again, 

 the calyx is sometimes furnished with an obscurely toothed . 

 or obsolete limb, and the student may, therefore, look for 

 the plant among those with incomplete flowers, and he will 

 not miss it, as the case is provided for; still he finds the 

 plant a second time among those with complete flowers. 

 Finally, a genus may be identified, although the investiga- 

 tion may be made from the apparent relations of the floral 

 parts, not from the true ones, as in Euphorbia. 



