Sacramento daily record-union. [volume] (Sacramento [Calif.]) 1875-1891, 1882-03-18

These two notifications in many cases in.
sensibly run into enc another. The I'm.
brauched tubes or ducts which interpene-
trate the cellular tissues of all of the
higher forms of vegetable life have been
termed vascular tissues. This vascular
tissue is formed by series of cells adher.
ing longitudinally together, thus forming
tube, generally obstructed by numerous
transverse sections, which are the remains
OF the end walls of the cells, and which,
by absorption or other processes often DIS
appear, thus leaving an unobstructed tube
OF considerable length. The first among
THR COMPLEX ORGANS
OF plant structure is the root The ten
dency ia with the roots of all except
very few plants to grow downward. as if in
obedience to the law of gravitation. The
growth of roots occur chiefly by leugthen.
ing, and is most manifest at the extremi-
ties. The extremity of every root is cap
ped by small cap or crown of old cells
Tals conical mass serves as an elastic
medium to protect the tender growing point
OF the root. 1t is by means of this root
cap That plants are enabled to penetrate
the soil. The cells of the root cap are
hlieo with AIR instead of with sap, and are
constantly wearing or slonghing away.
Just back of, and protected by the root
cap, Is narrow zone where the develop
ment and multiplication of the cells are for
the most part carried on. This zone con
stltutes the principal growing part Of the
roots, and is not at the very extremity
OF the root, but is Just behind
the extremity. The term root" does
not include all subterranean parts of
the plant instead, many Of the under
ground parts are only portions of the stem,
and which are often enlarged and filed
with starch or other matter. These under.
ground stems are characterized by the pres
eHce OF imbricated buds-the eyes of po-
tatoes, ariichokes, bulbs, etc.-on their
surface. The true roots have 90 traces of
buds, but sometimes the main root has pro.
tuberanses or marks at the points from
which the side roots grow. The structure
CT these protuberances has, however,
nothing IN common with the structure OF
true buds. The exogens or decotyledonous
plants, /. e. those whose growth takes place
By the addition of matter ON the exterior
of the wood and just under the bark, and
the embryo of which contains two cotyle-
dons, have at first simply descending
axes, the tap root, from which in the course
OF time branch out lateral roots with more
or less regularity. This tap root often
grows to great length they have been
found as much as forty feet long.
Other tap roots enter the soil only to very
short distance, and are exceeded In length
by the lateral roots. The province of the
tap roots seems to be to supply the plant
with the required amount Of water. Plants
have been grown experimentally with the
soil roots buried in medium devoid OF all
moisture, but which contained the other
materials requisite for plant growth, while
the tap root projected down into vessel
of water. The plants grew as well and
thriftily as those which had their entire
roots in moist soil. The function OF the
tap root explains the reason for the seem.
ingly abnormal (whcn compared to the size
of the plant length Of the tap root Of most
of the drought resisting plants, as well as
their ability to grow in soil which is desti-
tute of moisture to depth of several feet.
In some plants-beets, turnips, carrots,
etc.-the upper por ion of the tap roo ex-
pands and forms fleshy bulb in which is
stored up mass of nutritive matter for
tbs succeeding years growth.
ENDoGRNs OR ACKNOWLEDGEMENTS PLANTS
l. e, these which increase by inside
growth, and the embryo of which contains
but one cotyledon-the cereals, grasses,
maize, palms, etc.-have no tap roots, but
instead, mass of roots issue from a mar
- Yka1 e Il, b,
are known as crown roots, and are very
apparent in the onion and maize plants
The term rootlets is applied to the slender
roots which are formed last, and which
bear the same relation to the main root as
twigs do to the stem of a tree The offices
OF the root are threefoid First, to fix the
plant in the earth, and to MAINTAIN it in
Its normal position, generally upright
second, to minister to the growth of the
plant, absorbing nutriment from the soil
and, third, III many plants, especially
perennials, to lay up supply of food for
the future use OF the plant. The firm
ness with which plant is fixed in the
soil depends on the development of
the roots and mainly of the tap
root. The growth OF the roots is
in turn influenced by the depth and char
acter of the soil. In general the extent
and size of the roots may be said to be
commensurate with tie duties required of
them. Ii the size OF the tree is very great,
or the distance which the root must de-
scend or ramify in order to supply the
plant with water or nu!riment, is great,
then the root must of necessity be largely
developed in order to fulfill these require