34 POPULAR FIELD BOTANY. 
Il. ENDOGENS. 
FEndogens include all those plants the stem of which 
increases but little in thickness; it lengthens and be- 
comes harder by the introduction of new wood in the 
interior: whence its name Lndogens. The veins of the 
leaves are placed parallel, and the seed produces only 
one primary leaf; therefore the class is also called Mono- 
cotyledonous. Grasses are familiar examples. It is di- 
vided into two Sub-classes, Petaloide@ and Glumacea. 
lst SuB-cLASs. 
PeraLoripE&. The parts of which the flower is composed 
are placed in one or two rows, are generally coloured, 
and never immediately surrounded by bracteas. Di- 
vided into thirteen orders, as follows. 
1. Alismacee.—Calyx divided into three. Petals three. 
Stamens on the ovary. Carpels several, distinct, with 
one or two seeds. 
2. Butomacee.—F lowers in some measure like the last, but 
there are an indefinite number of ovules, or seeds. 
3. Juncaginacee.—Calyx and petals both herbaceous, rarely 
absent. Stamens six. Ovaries three or six, superior, 
