BOTANY 



OP THE 



NORTHERN UNITED STATES. 



SERIES I. 



PH^ENOGAMOUS OE FLOWEKING PLANTS. 



VEGETABLES bearing proper flowers, that is, having sta- 

 mens and pistils, and producing seeds, which contain an 

 embryo. 



CLASS I. DICOTYLEDONOUS OB EXOGE- 

 NOUS PLANTS. 



Stems formed of bark, wood, and pith ; the wood forming 

 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 netted- 

 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. ANGIOSPERM^E. 



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

 forms the fruit. Cotyledons only two. 

 3 



