BOTANY 
OF THE 
NORTHERN UNITED STATES. 
Series I. PH^GNOGAMOUS or FLOWERING 
PLANTS. 
Vegetables bearing proper flowers, with stamens 
and pistils, and producing seeds which contain an 
embryo. (Vide Introduction , supra, and Botanical 
Text-Book, pp. 318, 328.) 
Class I. DICOTYLEDONOUS or EXOGENOUS 
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 two or more opposite cotyledons. 
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