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THE ORGANIC CREATION.

LESSON I.

PLANTS.

element is supplied to the plant in three different forms: that of vapor which the plant absorbs,-that of liquid water by which some plants are surrounded, and that of moisture which HE term organic creation is the plant extracts, as nutriment from the earth. The developapplied to those objects which ment of plants is further dependent upon the chemical qualhave life, and are possessed of ities of the soil in which they live, whether it be composed parts, or organs. Organized of pure or mixed earths, or of soil rich in clay or vegetable bodies are either animals or mold. plants. With animals, the stomach is the organ of digestion, the lungs of respiration, the limbs of motion, etc. A plant is also composed of parts, as the root, bark, leaves, etc., which severally perform certain functions necessary to its existence and growth.

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533. Botanical Geography, or the "Geography of Plants," is a branch of natural science that treats of the laws which regulate the distribution of vegetable life over the surface of the earth. Plants occur over the whole globe under the most opposite conditions. They flourish in the bosom of the ocean as well as on land, under the extremes of cold and heat, in polar and equatorial regions, on the hardest rocks and in the most fertile valleys, amid the perpetual snow of lofty mountains and in springs at the temperature of boiling water, and in deep caverns where the sun has never sent a cheering ray.

534. The life and healthy growth of plants depend upon light, heat, and moisture. It is light that gives to plants that beautiful green color, the intensity of which increases with the brilliancy of the light. "Plants always turn toward the light; the guiding power we know not, but the evidence of some impulsive or attracting force is strong, and the purpose for which they are constituted to obey it is proved to be the dependence of vegetable existence upon luminous power."*

535. Heat is another essential which determines the condition of plants, by the amount of it which prevails during the season of vegetation. In the cold regions of very high latitudes vegetation scarcely exists, and even in the temperate zones its luxuriance is materially diminished by the severe climate of winter. The influence of heat on vegetable life is most strikingly exhibited on high mountains in the torrid zone, where the growth and luxuriance of plants diminish in proportion to elevation, and consequently in proportion to the diminution of heat.

537. It belongs to Botany, Vegetable Physiology, and Agricultural Chemistry to investigate the structure and nature of plants, and to examine in detail the treasures of the vegetable kingdom. The business of the physical geographer is to notice the disposition of the vegetable tribes, and the circumstances which seem to regulate their distribution.

538. Scarcely fourteen hundred species of plants appear to have been known by the Greeks and Romans. At the time of Linnæus (A.D. 1762) the number of known species was 8,800. In 1835, Lindley gave the number at 86,000. At the present time, according to Lyell, there have been collected upward of 100,000 species; and when we reflect that the interior of Africa, of Australia, and of the great islands of Oceanica have not been visited by the naturalist, it will not be deemed extravagant to estimate the total aggregate of species on the earth at 133,000.

539. "A species embraces all such individuals as may have originated from a common stock. Such individuals bear an essential resemblance to each other, as well as to their common parent, in all their parts. Thus the white clover is a species, embracing thousands of cotemporary individuals, scattered over our hills and plains, all of a common descent, and producing other individuals of their own kind from their seed."

540. The vegetable kingdom consists of two great natural divisions, namely, Phænogamia, or Flowering Plants, and Cryptogamia, or Flowerless Plants. The PHENOGAMIA possess a woody structure, have leafy appendages, develop flowers, and produce seeds. They have two subdivisions, depending upon their manner of growth, called Exogens and Endogens.

541. The Exogens (from exo, outside, and genesis, increase) are a class of flowering plants whose stems have bark, wood, and pith. The bark is increased by layers deposited within the previously formed layers, and the wood by layers or rings placed outside of those of the previous year. This class embraces the forest trees, as the oak, elm, pine, chestnut, poplar, hazel, willow, birch, etc., most of the flowering shrubs and herbs, as the arbutus, sage, mint; also the dahlia, artichoke, thistle, lettuce, marigold, dandelion, daisy, etc. They are also

536. Without moisture there can be no vegetation, and this called Dycotyledons, from the seed consisting of two lobes.

Questions.-532. To what is the term organic creation applied? What are organized bodies? Name some of the organs of animals? of plants? 583. What is Botanical Geography? Under what opposite conditions do plants flourish? 584. Upon what does the live, etc., of plants depend? What gives the green color to plants? 535. Where is the effect of heat on vegetation most strikingly exhibited? 536 What is said of moisture, and in what three forms is it applied to plants? Upon what else is the development of plants dependent? 587. What is the business of the physical geographer?

"The Poetry of Science," by Robert Hunt.

Questions.-588. How many species of plants were known by the Greeks and Romans? How many at the time of Linnæus in 1762? In 1885? How many have been collected at the present time? Probable number on the earth? 539. What is a species? Example. 540. Of what two great natural divisions does the vegetable kingdom consist? Describe the Phænogamia. What two subdivisions have the Phænogamia? 541. What are the Exogens? How are the bark and wood of this subdivision increased? What does this class embrace? By what other name are they called, and why?

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543. The Endogens (from endon, within, and genesis, to increase) are those which have their stems increasing from within, and present no separate appearance of wood, pith, and bark. They comprehend the numerous grasses, and the most important of all vegetable tribes, viz., the valuable pasture and all the grain-yielding plants, wheat, barley, oats, Indian corn, rice, sugar-cane, etc., with lilies and the palm family. They are also called Monocotyledons, from having only one seed-lobe.

SUGAR-CANE AND RICE.

544. The CRYPTOGAMIA, or flowerless plants, include mosses, lichens, fungi, ferns, sea-weeds, etc.

545. Station indicates the peculiar nature of the locality where each species is accustomed to grow, and has reference to climate, soil, humidity, light, elevation above the sea, etc.; by habitation is meant a general indication of the country where a plant grows wild. Thus the station of a plant may be a salt-marsh, a hillside, the bed of the sea, or a stagnant pool. Its habitation may be Europe, North America, or New Holland, between the tropics.

LESSON II.

DISTRIBUTION OF PLANTS.

546. In considering the distribution of the vegetable species it is important to observe the distinction between indigenous and exotic plants. The former are the native productions of a country; the latter are those which have been introduced from abroad. The number of exotic plants is comparatively small. They consist, for the most part, of those species which are eminently useful to man in furnishing him food, the materials for clothing, etc., besides a variety of flowering plants and

shrubs.

547. The indigenous class comprehends the great proportion of the vegetable species which adorn the surface of the globe. It includes many useful plants which can not be successfully transplanted to foreign climes; but by far the greater number

Questions.-542. How may the age of an exogenous tree be determined? Ages of several species of trees? 543. What are the Endogens? What do they comprehend? By what other name are they called, and why? 544. What do the Cryptogamia include? 545. What does station indicate? Habitation? Illustrate. 546 What are indigenous plants? Exotic plants? Of what species do the exotics, for the most part, consist? 547. What does the indigenous class comprehend? What does it include? 548. What has been ascertained respecting the indigenous plants?

are those which are not so especially serviceable to man, and hence there is no inducement to transfer them from the countries in which they are naturally found.

548. Of the indigenous plants, it has been ascertained that different regions are inhabited by distinct species. This fact is strikingly exhibited by an examination of New Holland, where they are found to be, almost without exception, distinct from those known in other parts of the world. Countries situated between the same parallels of latitude differ essentially in their species of vegetation. Out of 2,891 species of flowering plants observed by a naturalist in the United States, there were only 385 which are found in northern or temperate Europe. Humboldt and Bonpland, in all their travels in equinoctial America, found only twenty-four species common to America and any other part of the world.

549. It is a remarkable fact, that in the more widely separated parts of the Eastern Continent, notwithstanding the existence of an uninterrupted land communication, the diversity of species is almost as striking as between countries separated by wide oceans. Thus there is found one assemblage of species in China, another in the countries bordering the Black Sea and the Caspian, a third in those surrounding the Mediterranean, a fourth in the great platforms of Siberia and Tartary, and so forth.

550. By the term botanical province is meant a district the vegetation of which consists in great part of species confined to the limits of that district. Twenty-five great botanical provinces have been established, although many of these contain a variety of species which are common to several others. Professor Martius, of Munich, has divided the vegetation of the globe into 51 provinces, namely, 5 in Europe, 11 in Africa, 13 in Asia, 3 in New Holland, 4 in North America, and 8 in South America, besides the province of Central America, the Antilles, the Antarctic Lands, New Zealand, Van Diemen's Land, New Guinea, and Polynesia.

551. "The first travelers were persuaded that they should find, in distant regions, the plants of their own country, and they took a pleasure in giving them the same names. It was some time before this illusion was dissipated; but so fully sensible did botanists at last become of the extreme smallness of the number of phænogamous plants common to different continents, that the ancient floras fell into disrepute. All grew diffident of the pretended identification; and we now find that every naturalist is inclined to examine each supposed exception with scrupulous severity. If they admit the fact, they begin to speculate on the mode whereby the seeds may have been transported from one country to the other, or inquire on which of two continents the plant was indigenous, assuming that a species, like an individual, can not have two birthplaces."

552. Plants are diffused in a variety of ways. The principal of the inanimate agents provided by nature for scattering the seeds of plants over the globe are the movements of the atmosphere and of the ocean, and the constant flow of water from the mountains to the sea. A great number of seeds are furnished with downy and feathery appendages, enabling them, when ripe, to float in the air, and to be wafted easily to great distances by the most gentle breeze. As winds often prevail for days and weeks, or even months together, in the same

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Questions.-What is said of the vegetation of different countries situated between the same parallels of latitude? Illustrate. 549. What is said of the diversity of species in the Eastern Continent? Illustrate. 550. What is meant by the term botanical province? How many botanical provinces have been established? 552. What are the principal inanimate agents employed in scattering the seeds of plants? Explain the agency of winds.

*Lyell's "Principles of Geology."

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favorable. that they might have vegetated had the climate and soil been are indigenous to America and the West Indies, in such a state

life upon the surface of the globe. of their joint influence in distributing the forms of vegetable for thousands of years, we can not doubt the immense effect ers. When we reflect that these causes have acted incessantly of plants preserved in their gizzards, or attached to their feathtween different countries, and convey to and fro the seeds by migratory birds, which every year alternate in millions be555. The diffusion of the vegetable species is also promoted

into every region whither quadrupeds may migrate. remain attached for weeks, or even months, and are borne along which they are provided, to the coats of animals, to which they Some kinds adhere, by means of prickles, hooks, and hairs, with 554. Seeds are also distributed by the agency of animals.

the parent plant. there is a station fitted for them. the atmosphere, and carried to any point of the globe where no difficulty in accounting for their being dispersed throughout cles of which are scarcely visible to the naked eye, and there is mosses, fungi, and lichens, consist of a fine powder, the partiwhich prevail in some regions. The germs of many plants, as through considerable spaces by the hurricanes and whirlwinds Even the heavier grains may be borne direction, such seeds may be conveyed to a great distance from

of America. western coasts of Europe the fruits and seeds of plants which shores of the Atlantic by seeds that generated in the interior The Gulf Stream is known to convey to the seeds which grew in the interior of Germany, and the western them. Thus the southern shores of the Baltic are visited by down to the valleys the seeds which may accidentally fall into 553. Rivers aid in the distribution of vegetation by bringing

QUESTIONS ON THE MAP.

SUPERFICIAL DISTRIBUTION OF PLANTS.

Do trees grow as far north as the arctic coasts of the conti-
nents? Does their range extend north of the Arctic circle across
most of the Eastern Continent? Of the Western Continent?
Are Iceland and the south point of Greenland within the range
of trees? About midway on the eastern shore of what great bay
does the northern limit of trees reach its lowest latitude?

What is the region north of this limit termed on the map?
What are saxifrages? Ans. A genus of hardy herbs growing on or
among rocks. What distinguishes, in respect to man, the region
of saxifrages etc. from that farther south? Ans. The absence
of all cultivation. What plants are found in Melville Island?
Which of these orders includes various species that extend
to the borders of perpetual snow? Ans. Lichens.
What are
lichens? Ans. A kind of plants including those familiarly known as
rock moss and tree moss, growing im thin flat crusts, and other humble
forms, on hard surfaces. We have noticed [page 68] that the climate
of Spitzbergen is much warmer than that of Melville Island,-
what plants mentioned on the map in connection with the former
are not named with the latter? What important food-plant is
cultivated in Iceland and the southern part of Greenland?

What three cereal grains grow farthest north? On the west
coast of what grand divisions does their northern limit nearly
reach that of trees? What valuable fibrous plants are culti-
vated nearly as far north? [See perpendicular line marking their

latitudinal range in the eastern part of Europe.]

What causes referred to in the map-questions before studied
may be assigned for the high northern range of the above
plants in western Europe? Near the mouth of what great river
in America and about midway on the west coast of what coun-
try in Europe is the northern limit of wheat? The northern
limit of what important forest-tree nearly coincides with this, in
the Eastern Hemisphere? What valuable fruit-trees have this
limit near that of the oak, in western Europe? [See perpendicular
over the Atlantic, marking their latitudinal range.] The northern limit
of what important grain barely exceeds the latitude of the south-
ern part of the British Isles? That of what fruit-bearing plant
extends not far from this, in the Eastern Hemisphere?

Does the range of the cultivation of rice extend into southern
Europe? Is it mostly confined, in this grand division, to the
warm Mediterranean regions? Does it embrace much territory
in America? The northern limit of what rich fruits, in the Old
World, is between that of rice and the vine? [See perpendicular
line over the Atlantic, marking their latitudinal range.] Does the limit
of rice in the Southern Hemisphere extend far south of the Tropic
of Capricorn? The cultivation of what important plants in both
the Old and New World is chiefly within the latitudinal range
of rice? Does the northern limit of palms extend mostly north
or south of that of the cultivation of rice? Which has the most
northern range, as an object of culture, palms or rice? What
country of South America lies south of the range of wheat
What important plants in the New World have their range
mostly within the tropics? [See perpendicular over the Pacific, show-
ing their latitudinal extent.]

In what part of America is the cocoa tree cultivated? Where
do Peruvian bark trees grow? What flourish in Polynesia? Do
they thrive in parts of Oceanica, near the Old World?

What plant occupies a limited district in southeastern Asia,
mostly north of the Tropic of Cancer? What kinds of vegeta-
tion distinguish the islands and parts of the peninsulas on the
northeast of the Indian Ocean? What tree has its favorite range
in the lower extremity of Arabia and the part of Africa lying to
the southward? What valuable food-plants flourish in Central
Africa? What grow on the western coast of Africa? What is
the character of the baobab? Ans. It is a low, wide-spreading tree, the
trunk of which grows to a thickness, in some cases, of from twenty-five to
thirty and even thirty-two feet, and which affords a valuable bark and fruit,
but is chiefly remarkable for the great age it attains [see page 71].

VERTICAL DISTRIBUTION OF PLANTS.

The range of what trees in the torrid zone extends to the
height of about one mile (5,280 feet) above the sea? Of what
tree in the middle region of the temperate zone? At nearly what
height does the oak cease to flourish in the torrid zone? What
cereal grain grows on the Andes near the equator to an altitude
of 12,000 feet? What one, from a moderate elevation, to nearly
15,000 feet? To what altitude on the Himalayas does barley
grow? What forests reach their limit on these mountains about
3,000 feet above that of barley?

How high is the limit of trees on the Alps or in the middle
region of the temperate zone? What food-plant is cultivated a
little below that limit or at an altitude of about one mile?

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557. "The date-palm has been introduced from Africa into the south of Spain. The grapevine, now so common in western Europe, has been

naturalized from western Asia. The coffee-bush, native to the highlands

of Ethiopia, was taken thence to the scene of its present cultivation. the southern part of the Arabian peninsula; and the culture of the tea-plant, indigenous to China, has recently been attempted with success in the south of France. Rice, known in the southern regions of Asia from the remotest antiquity; the valuable bread-fruit tree, indigenous in the same district, and in the Polynesian Islands; and the more important cereals, wheat, barley, oats, and rye, have all been transferred from the Old World to the New since the discovery of the latter by Europeans."

558. "In return, the Old World has received from the New, maize or Indian corn, and the potato, the cultivation of which extends from Lapland to the extremity of Africa. Our principal fruit trees appear to have traveled into Europe and Great Britain from Syria; the damson plum, with the damask rose, as their names import, from the neighborhood of Damascus; the cherry from Pontus; the walnut and the peach from Persia; the apricot from Armenia; the citron, lemon, and orange from the warmer parts of Asia."

110

the extreme limits of culture in Lapland, to the heights immediately beneath the equator, but it is only in a narrow zone of the northern hemisphere that it is reared as the sole breadgrain; beside it appear Rye, which is the peculiar bread-grain in Norway, Sweden, Finland, and the northern part of Russia; and Oats, which are extensively cultivated throughout northern Europe. These grains are also cultivated in North America, though chiefly confined to British America and the northern part of the United States.

562. Wheat is the prevailing cultivated plant in Great Britain, Germany, France, and a wide range toward the east, including the whole of the region of the Caspian; in the basin of the Mediterranean, and throughout North America, it is associated with maize. Its northern limit in America is unknown, the country being uninhabited; but at Cumberland House, in the very middle of the continent, one of the stations of the Hudson Bay Company, in 54° north latitude, there are fields of wheat,

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NOTE.-The map-questions on page 73 should receive at- barley, and Indian corn. Wheat thrives luxuriantly in Chile tention before proceeding with the following lesson.

LESSON III.

FOOD PLANTS.

559. MAN, in almost every country, has selected annual plants for food; that is, such plants as complete their whole vegetative processes within the course of a few months. These, for the most part, possess a subterraneous and usually tuberous stem, which sends up shoots above the soil; after some time flowers appear, and afterward fruit. During the remainder of the year the plants sleep, as it were, beneath a protecting coverlet of earth, and are thus beyond the influence of excessive heat or cold. By the cultivation of these plants, man has rendered himself independent of the destroying action of the dry season in semi-tropical regions, and of the killing influence of the winter cold in higher latitudes. It is remarkable that there are only three arborescent vegetables in the whole world which can be included among the chief food-plants, namely, the bread-fruit, the cocoa-nut, and the date, and these have become objects of culture, and furnish in certain regions the principal food of large bodies of men.

360. The most common food-plants are as follows: In the Old World the species which prevail are the grains, or cereal grasses, namely, barley, oats, rye, wheat, rice, millet, sorghum, and the olive. The trees are the date-palm, banana, cocoa-nut, bread-fruit, and the pandanus. In the New World the species which have their origin are maize, potato, manioc, and arrowroot. The food-plants cultivated to a certain extent in both continents are sugar, coffee, tea, the vine, cocoa, pepper, cinnamon, cloves, nutmegs, and cassia.

561. The regions over which these plants are distributed may be seen by inspection of Map 4. They range from the poles toward the equator in the following order. Barley, which has the widest distribution of all the cerealia, is cultivated from Quest lons.-559. What plants has man selected for his food? What is said of these plants? Which are the only three arborescent vegetables included among the chief foodplants? 560. What species of food-plants prevail in the Old World? The trees?

Rev. Thomas Milner.

and Rio de la Plata, and at elevations of 8,500 and 10,000 feet above the sea. It even produces grain on the banks of Lake Titicaca in the Peru-Bolivian Andes, at the absolute height of 12,795 feet, in sheltered situations. Buckwheat is a plant of tolerably extensive culture in the northern temperate zone. It is a native of Asia, from whence it was brought into Europe in the fifteenth century.

563. Maize or Indian Corn is much cultivated in Europe and America south of the 47th parallel of latitude. In the United States great attention is paid to the culture of this grain, of which there were produced, in 1860, over 830 million bushels. Rice has been cultivated in the southern regions of Asia from the earliest ages. It constitutes the staple food of the inhabitants of the Indian peninsulas, China, Japan, and the East Indian Islands. Rice is the food of a greater number of human beings than any other grain. It requires excessive moisture, and a temperature of 73° at least; consequently its cultivation is limited to countries between the equator and the 45th parallel.

564. The Olive in the Old World embraces two zones or bands, north and south of the equator, about 9° in width, from latitude 35° to latitude 44°. The climate of the New World, which is subject to the extremes of heat and cold, is not favorable to the cultivation of this plant. The Date-Palm yields one of the most nourishing fruits in existence. It grows spontaneously on the southern slopes of the Atlas chain, on the banks of the Nile, and in the Canary Islands; its range extends to Palestine and Hindoostan, and it has been introduced into the south of Spain. It is said that each tree yields annually from 150 to 260 pounds of fruit.

Questions.-What species have their origin in the New World? What food-plants are cultivated to a certain extent in both continents? 561. What is the region of barley? Rye? Oats? 562. Wheat? Its northern limit in America? At what elevation does it grow in South America? Buckwheat? 568. Maize or Indian corn? Rice? What does its enltivation require? 564 The olive? Date-palm"

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