NORTH AMERICA.
I. CORMOPHYTA. E ndlicher.
Dicotyledones, Monocotyledones, and Acotyledones in part, Juss.
P lants consisting of a root and stem growing in opposite
directions, composed o f regular cellular tissue
traversed (ex cep t in the very low est forms) by woody
fibre and vessels. S tem increasing in siz e either at the
apex and circumference simultaneously, or at the apex
solely, producing buds, and (w ith few exceptions) distinct
leaves at definite points and in regular order : the
cuticle usually furnished with stomata. P ropagation
effected by means of flowers and seeds in the higher
forms, and of spores in the lower.
Class I. EXOGENOUS OR DICOTYLEDONOUS
PLANTS.
F l o w e r in g plants.—S t em with a distinct bark and pith, separated
from each other by an interposed zone consisting of woody
fibre, ducts, and spiral vessels: increase in diameter effected by
the successive deposition, between the old wood and the bark, of
new woody and cortical matter, which in perennial trunks is
usually arranged in concentric zones, and traversed by medullary
rays. L eaves furnished with stomata, commonly articulated with
the stem, their veins branching and reticulated. F loral enve