BOTANY 



OF THE 



NORTHERN UNITED STATES. 



SERIES I. 



FH^ENOGAMOUS or FLOWERING PLANTS. 



Vegetables bearing proper flowers, that is, having sta- 

 mens and pistils, and producing seeds, which contain an 

 embryo. * 



Class I. DICOTYLEDONOUS or EXOGE- 

 NOUS PLANTS. 



Stems formed of bark, wood, and pith ; the wood form- 

 ing a layer between the other two, increasing, when the 

 stem continues from year to year, by the annual addition 

 of a new layer to the outside, next the bark. Leaves net- 

 ted-veined. Embryo with a pair of opposite cotyledons, 

 or rarely several in a whorl. Flowers having their parts 

 usually in fives or fours. 



Subclass I. ANGIOSPER1VLE. 



Pistil consisting of a closed ovary, which contains the ovules and 

 forms the fruit. Cotyledons only two. 



