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PREFACE.
PREFACE.
The rapid advances made in the science of botany within the last few years necessitate changes in the text books in use as well as in methods of teaching. Having, in his own experience as a teacher, felt the need of a book different from any now in use, the author has prepared the present volume with a hope that it may serve the purpose for which it is intended; viz., an introduction to the study of botany for use in high schools especially, but sufficiently comprehensive to serve also as a begi
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CHAPTER I. INTRODUCTION.
CHAPTER I. INTRODUCTION.
All matter is composed of certain constituents (about seventy are at present known), which, so far as the chemist is concerned, are indivisible, and are known as elements. Of the innumerable combinations of these elements, two general classes may be recognized, organic and inorganic bodies. While it is impossible, owing to the dependence of all organized matter upon inorganic matter, to give an absolute definition, we at once recognize the peculiarities of organic or living bodies as distinguish
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CHAPTER II. THE CELL.
CHAPTER II. THE CELL.
If we make a thin slice across the stem of a rapidly growing plant,— e.g. geranium, begonia, celery,—mount it in water, and examine it microscopically, it will be found to be made up of numerous cavities or chambers separated by delicate partitions. Often these cavities are of sufficient size to be visible to the naked eye, and examined with a hand lens the section appears like a piece of fine lace, each mesh being one of the chambers visible when more strongly magnified. These chambers are know
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CHAPTER III. CLASSIFICATION OF PLANTS.—PROTOPHYTES.
CHAPTER III. CLASSIFICATION OF PLANTS.—PROTOPHYTES.
For the sake of convenience it is desirable to collect into groups such plants as are evidently related; but as our knowledge of many forms is still very imperfect, any classification we may adopt must be to a great extent only provisional, and subject to change at any time, as new forms are discovered or others become better understood. The following general divisions are usually accepted: I. Sub-kingdom (or Branch); II. Class; III. Order; IV. Family; V. Genus; VI. Species. To illustrate: The w
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CHAPTER IV. SUB-KINGDOM II. Algæ.[3]
CHAPTER IV. SUB-KINGDOM II. Algæ.[3]
In the second sub-kingdom of plants is embraced an enormous assemblage of plants, differing widely in size and complexity, and yet showing a sufficiently complete gradation from the lowest to the highest as to make it impracticable to make more than one sub-kingdom to include them. They are nearly all aquatic forms, although many of them will survive long periods of drying, such forms occurring on moist earth, rocks, or the trunks of trees, but only growing when there is a plentiful supply of wa
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CHAPTER V. Green Algæ—Continued.
CHAPTER V. Green Algæ—Continued.
The Conjugatæ , while in some respects approaching the Confervaceæ in structure, yet differ from them to such an extent in some respects that their close relationship is doubtful. They are very common and familiar plants, some of them forming great floating masses upon the surface of every stagnant pond and ditch, being commonly known as “pond scum.” The commonest of these pond scums belong to the genus Spirogyra , and one of these will illustrate the characteristics of the order. When in active
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CHAPTER VI. THE BROWN ALGÆ (Phæophyceæ).
CHAPTER VI. THE BROWN ALGÆ (Phæophyceæ).
Fig. 24. —Forms of diatoms. A , Pinnularia . i , seen from above; ii , from the side. B , Fragillaria (?). C , Navicula . D , F , Eunotia . E , Gomphonema . G , Cocconeis . H , Diatoma . All × 300. These plants are all characterized by the presence of a brown pigment, in addition to the chlorophyll, which almost entirely conceals the latter, giving the plants a brownish color, ranging from a light yellowish brown to nearly black. One order of plants that possibly belongs here ( Diatomaceæ ) are
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CHAPTER VII. Class III.—The Red Algæ (Rhodophyceæ).
CHAPTER VII. Class III.—The Red Algæ (Rhodophyceæ).
These are among the most beautiful and interesting members of the plant kingdom, both on account of their beautiful colors and the exquisitely graceful forms exhibited by many of them. Unfortunately for inland students they are, with few exceptions, confined to salt water, and consequently fresh material is not available. Nevertheless, enough can be done with dried material to get a good idea of their general appearance, and the fruiting plants can be readily preserved in strong alcohol. Specime
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CHAPTER VIII. SUB-KINGDOM III. Fungi.
CHAPTER VIII. SUB-KINGDOM III. Fungi.
The name “Fungi” has been given to a vast assemblage of plants, varying much among themselves, but on the whole of about the same structural rank as the algæ. Unlike the algæ, however, they are entirely destitute of chlorophyll, and in consequence are dependent upon organic matter for food, some being parasites (growing upon living organisms), others saprophytes (feeding on dead matter). Some of them show close resemblances in structure to certain algæ, and there is reason to believe that they a
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CHAPTER IX. THE TRUE FUNGI (Mycomycetes).
CHAPTER IX. THE TRUE FUNGI (Mycomycetes).
The great majority of the plants ordinarily known as fungi are embraced under this head. While some of the lower forms show affinities with the Phycomycetes , and through them with the algæ, the greater number differ very strongly from all green plants both in their habits and in their structure and reproduction. It is a much-disputed point whether sexual reproduction occurs in any of them, and it is highly probable that in the great majority, at any rate, the reproduction is purely non-sexual.
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CHAPTER X. Fungi—Continued.
CHAPTER X. Fungi—Continued.
The Basidiomycetes include the largest and most highly developed of the fungi, among which are many familiar forms, such as the mushrooms, toadstools, puff-balls, etc. Besides these large and familiar forms, there are other simpler and smaller ones that, according to the latest investigations, are probably related to them, though formerly regarded as constituting a distinct group. The most generally known of these lower Basidiomycetes are the so-called rusts. The larger Basidiomycetes are for th
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CHAPTER XI. SUB-KINGDOM IV. Bryophyta.
CHAPTER XI. SUB-KINGDOM IV. Bryophyta.
The Bryophytes, or mosses, are for the most part land plants, though a few are aquatic, and with very few exceptions are richly supplied with chlorophyll. They are for the most part small plants, few of them being over a few centimetres in height; but, nevertheless, compared with the plants that we have heretofore studied, quite complex in their structure. The lowest members of the group are flattened, creeping plants, or a few of them floating aquatics, without distinct stem and leaves; but the
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CHAPTER XII. SUB-KINGDOM V. Pteridophytes.
CHAPTER XII. SUB-KINGDOM V. Pteridophytes.
If we compare the structure of the sporogonium of a moss or liverwort with the plant bearing the sexual organs, we find that its tissues are better differentiated, and that it is on the whole a more complex structure than the plant that bears it. It, however, remains attached to the parent plant, deriving its nourishment in part through the “foot” by means of which it is attached to the plant. In the Pteridophytes, however, we find that the sporogonium becomes very much more developed, and final
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CHAPTER XIII. CLASSIFICATION OF THE PTERIDOPHYTES.
CHAPTER XIII. CLASSIFICATION OF THE PTERIDOPHYTES.
There are three well-marked classes of the Pteridophytes: the ferns ( Filicinæ ); horse-tails ( Equisetinæ ); and the club mosses ( Lycopodinæ ). The ferns constitute by far the greater number of pteridophytes, and their general structure corresponds with that of the maiden-hair fern described. There are three orders, of which two, the true ferns ( Filices ) and the adder-tongues ( Ophioglossaceæ ), are represented in the United States. A third order, intermediate in some respects between these
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CHAPTER XIV. SUB-KINGDOM VI. Spermaphytes: Phænogams.
CHAPTER XIV. SUB-KINGDOM VI. Spermaphytes: Phænogams.
The last and highest great division of the vegetable kingdom has been named Spermaphyta , “seed plants,” from the fact that the structures known as seeds are peculiar to them. They are also commonly called flowering plants, though this name might be also appropriately given to certain of the higher pteridophytes. In the seed plants the macrosporangia remain attached to the parent plant, in nearly all cases, until the archegonia are fertilized and the embryo plant formed. The outer walls of the s
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CHAPTER XV. SPERMAPHYTES.
CHAPTER XV. SPERMAPHYTES.
The angiosperms include an enormous assemblage of plants, all those ordinarily called “flowering plants” belonging here. There is almost infinite variety shown in the form and structure of the tissues and organs, this being particularly the case with the flowers. As already stated, the ovules, instead of being borne on open carpels, are enclosed in a cavity formed by a single closed carpel or several united carpels. To the organ so formed the name “pistil” is usually applied, and this is known a
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CHAPTER XVI. CLASSIFICATION OF THE MONOCOTYLEDONS.
CHAPTER XVI. CLASSIFICATION OF THE MONOCOTYLEDONS.
In the following chapter no attempt will be made to give an exhaustive account of the characteristics of each division of the monocotyledons, but only such of the most important ones as may serve to supplement our study of the special one already examined. The classification here, and this is the case throughout the spermaphytes, is based mainly upon the characters of the flowers and fruits. The classification adopted here is that of the German botanist Eichler, and seems to the author to accord
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CHAPTER XVII. DICOTYLEDONS.
CHAPTER XVII. DICOTYLEDONS.
Fig. 92. —End of a branch of a horsechestnut in winter, showing the buds covered by the thick, brown scale leaves, × 1. The second sub-class of the angiosperms, the dicotyledons, receive their name from the two opposite seed leaves or cotyledons with which the young plant is furnished. These leaves are usually quite different in shape from the other leaves, and not infrequently are very thick and fleshy, filling nearly the whole seed, as may be seen in a bean or pea. The number of the dicotyledo
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CHAPTER XVIII. CLASSIFICATION OF DICOTYLEDONS.
CHAPTER XVIII. CLASSIFICATION OF DICOTYLEDONS.
Nearly all of the dicotyledons may be placed in one of two great divisions distinguished by the character of the petals. In the first group, called Choripetalæ , the petals are separate, or in some degenerate forms entirely absent. As familiar examples of this group, we may select the buttercup, rose, pink, and many others. Fig. 96. —Iulifloræ. A , male; B , female inflorescence of a willow, Salix ( Amentaceæ ), × ½. C , a single male flower, × 2. D , a female flower, × 2. E , cross-section of t
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CHAPTER XIX. CLASSIFICATION OF DICOTYLEDONS (Continued). Division II.—Sympetalæ.
CHAPTER XIX. CLASSIFICATION OF DICOTYLEDONS (Continued). Division II.—Sympetalæ.
The Sympetalæ or Gamopetalæ are at once distinguished from the Choripetalæ by having the petals more or less united, so that the corolla is to some extent tubular. In the last order of the Choripetalæ we found a few examples ( Mimosaceæ ) where the same thing is true, and these form a transition from the Choripetalæ to the Sympetalæ . There are two great divisions, Isocarpæ and Anisocarpæ . In the first the carpels are of the same number as the petals and sepals; in the second fewer. In both cas
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CHAPTER XX. FERTILIZATION OF FLOWERS.
CHAPTER XX. FERTILIZATION OF FLOWERS.
If we compare the flowers of different plants, we shall find almost infinite variety in structure, and this variation at first appears to follow no fixed laws; but as we study the matter more thoroughly, we find that these variations have a deep significance, and almost without exception have to do with the fertilization of the flower. In the simpler flowers, such as those of a grass, sedge, or rush among the monocotyledons, or an oak, hazel, or plantain, among dicotyledons, the flowers are extr
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CHAPTER XXI. HISTOLOGICAL METHODS.
CHAPTER XXI. HISTOLOGICAL METHODS.
In the more exact investigations of the tissues, it is often necessary to have recourse to other reagents than those we have used hitherto, in order to bring out plainly the more obscure points of structure. This is especially the case in studies in cell division in the higher plants, where the changes in the dividing nucleus are very complicated. For studying these the most favorable examples for ready demonstration are found in the final division of the pollen spores, especially of some monoco
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NATURAL SCIENCE.
NATURAL SCIENCE.
A Text-book for High Schools and Academies. By Alfred P. Gage , A.M., Instructor in Physics in the English High School, Boston. 12mo. 424 pages. Mailing Price, $1.25; Introduction, $1.12; Allowance for old book, 35 cents. T his treatise is based upon the doctrine of the conservation of energy , which is made prominent throughout the work. But the leading feature of the book—one that distinguishes it from all others—is, that it is strictly experiment-teaching in its method; i.e. , it leads the pu
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