GROWTH OF MONOCOTYLEDONS. 
113 
represent the fibers); eacli of these fibers seems to vegetate 
separately, they are ranged around a central support and are 
so disposed that the oldest are crowded outwardly, by the de- 
velopment of new fibers in the center of the stem ; this pres- 
sure causes the external layers to be very close and compact. 
This mode of increase, little favorable to growth in diameter, 
produces long and straight stems, nearly uniform in size 
itliroughout their whole extent ; as the palms and sugar-canes 
of the tropics, and the Indian corn of our climate. 
Fig. 127, at A, represents a section of the stipe or stem of a palm-tree; at B, ia 
the same magnified ; a b shows a part of the stipe in which the woody fibers are 
most dense and hard ; h c sliows the fibers less numerous, less compact, and lesa 
hard ; c d includes the woody fibers, tender and scattered ; the orifices of tubes 
/ g 
which have disappeared are seen at c a. In the part c d the celluhir tissue occu 
pies a greater space than at c b, and much more than at b a, where the woody 
fiber, or vascular texture, predominates. The fibers at e are of neAV formation ; aty 
they are older ; and at g still more ancient ; thus the development of the wood in 
this plant proceeds inversely to that of dicotyledonous plants. 
136. Endogenous plants continue to increase in hight long 
after they cease to grow in diameter ; the stem is gradually 
extended upward by new terminal shoots, which are formed 
annually. The epidermis is formed of the foot-stalks of leaves, 
which annually sprout from the rim of a new layer of wood ; 
tlie leaves falling in autumn, their foot-stalks become indurated, 
and remain upon the outer surface of the plant. 
137. By attention to the vegetable s(ruct.ire the young may be induced to 
think more upon the wonderful mechanism of th^ir own material frames, upon the 
analogy and yet infinite difference between themselves and the lilies of the field. 
In considering these things we are led to exclaim, in the language of the Psalniist, 
" Oh Lord, how manifold are thy works ! in wisdovn hast thou made them &11 !" 
The human body is nourished by the same elements as the grass which perish- 
eth ; the flowers have a much more refined corporeal substance, but how much 
more precious are we in the sight of the Almighty I Z)o we ack vhy we are of 
What is F'g, 127 designed to illustrate ? — 136. Endogenous stem :ne» ■<i*.'t^ "n l-i^hi, -How is th» 
opidermis fcmed / — 137. Reflections on tJu analogies between the v.-gevTbif a. I x-imfJ subslanci;3 
