STRUCTURE OF PLANTS. 
hand, and those of the useful plants on the other, man is enabled to select the materials 
proper to be used in accordance with his varying needs. It is easy to eat too much of plants 
that contain sulphur, lime, phosphorous, fatty, carbonaceous matter, or any other of the 
chemical ingredients of plants, when the system may really demand the use of those 
endowed with quite different properties; hence the value of this knowledge. 
It is truly wonderful that an order of plants, containing perhaps several hundred 
genera and many thousand species, will maintain, throughout all their variety of form and 
color, a predominance of one or more chemical elements. For instance, the Crucifer®, or 
Mustard family, one of great utility to man, every member of which affords nutritious 
and medicinal benefits, principally anti-scorbutic, or scurvy-destroying, in character. 
They all contain nitrogen and sulphur more largely than other plants, which accounts for 
their yielding ammonia when undergoing decay, as well as for their blood-purifying prop¬ 
erties. Many of our familiar table condiments, as mustard, horseradish, cress, etc., belong 
to this order. The Crucifer® are natives of the temperate zone, and are a natural antidote 
for the excessive use of fat-producing matters, so common in those regions. 
The order Leguminos® is perhaps the largest of all, and is remarkable for containing 
lime, albumen and starch. Its value in the animal economy is great, as it furnishes the 
bone and sinew, which constitute the essential framework of the animal structure. Like 
the other useful plants, they are found everywhere, to meet the necessities of universal 
animal life, while the poisonous or dangerous plants are confined to a very limited range. 
The Leguminos® are also possessed of many well-known medicinal properties, whose 
value can scarcely be overestimated. Plants yield about thirty-four different products, 
such as resin, oil, wax, gluten, starch, sugar, etc.; and at least eight well-known acids, 
viz.: oxalic in rhubarb, tartaric in grapes, citric in lemons, malic in apples, gallic in 
oak, benzoic in balsam, prussic or hydrocyanic in almonds, and phosphoric in oats. 
Vegetable chemistry, as may be conjectured from the remarks already made, is much 
too extensive a subject to receive proper attention in a subsidiary paragraph of a popular 
work devoted mainly to the poetry and cultivation of flowers; but this much it has been 
thought desirable to insert as a slight hint on an important subject, and a stimulus to 
further investigation. 
For the more easy comprehension of the general principles of botany by the unsci¬ 
entific lover of flowers, it is now proposed to consider the individual plant under the various 
relations of its internal structure, and its component parts viewed externally, together with 
the more important subdivisions of these, in a natural sequence, and in as few words as 
possible. What plants are composed of becomes then the next subject for consideration. 
TISSUES. 
Plants are made up of innumerable minute sacs, called cells, and generally of a lot 
of tubes or vessels, which were also originally rows of these cells, the whole constituting 
the material substance of plants, or what is technically known as tissue. The nourishment 
of plants passes from^cell to cell through the thin membranes that constitute the cell walls. 
These cells are of a definite structure, as found by microscopic observation, and the tissues 
are of different kinds according to the structure and arrangement of the cells and tubes. 
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