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THE ASSEMBLAGE OF LIVING CREATURES. 357
nature of the animal and the plant; but on developing, they soon exhibit,
by their structure and mode of life, the kingdom to which they belong.
It is the vegetable kingdom in particular that peoples and embellishes our
earth, thanks to the abundance of its species, the richness of its forms and
colors, and the vast dimensions of its trees, some of which, like the Sequoia
and the Eucalyptus, rise to more than three hundred feet high into the
region of the clouds. But how does the planet produce the innumerable
living bodies on its surface, from the green conferva, which germinates on
ponds, to man, who, proud of his strength, bravely meets his destiny ?
This is the great problem which excites the attention of the learned, and
which is not, perhaps, altogether insoluble. The subject has given rise
to much discussion, and to many experiments by chemists and biologists,
without at present any definite result being arrived at.
Botanists have not yet had time to count the prodigious number of
plants which surround us, from the great oak, with spreading foliage, to
the humble lichen, spread on the ground like a stain of blood. Besides,
if the multitude ofthe vegetable species have not yet been computed, it
must also be said that they are not yet agreed on the definition of species, some seeing simply varieties where others find absolutely distinct
characters. A century ago, Linnaeus knew only 6000 species; the lists
have since gradually increased in proportion as the various regions of the
earth have been more and more explored, and now the total number of
plants contained in the herbaria is estimated at about 12,000;* the increase has thus been, on an average, about a thousand each year. As to
the numerous species which botanists have not yet classified, nor even discovered, we can only judge by proportion ofthe probable figure. It is
thus that M. Alphonse de Candolle has been able to fix, in a general manner, the number of 400,000 to 500,000 species (250,000 being phanerogams)
for the whole of the terrestrial flora. Up to our days, therefore, hardly a
quarter of our riches has been recognized in the great inventory of the
vegetable productions of the globe; and not a year passes without important discoveries being made by travelers in different parts of the
world. Even the best known countries of Europe, which botanists have
not ceased to explore for a century, present every year new species to fortunate collectors of plants.
Of the number of classified species, already so considerable, the greatest
part, or about two-thirds, is composed of dicotyledonous phanerogams—
that is to say, of plants with visible flowers, and springing from the ground
with at least two primordial leaves: these are the highest species of the
vegetable series. Of the third which remains in the whole of terrestrial
vegetation, about a half consists of monocotyledons—that is to say, of
plants which have also apparent flowers, but which spring up with a single seed-leaf: such are palms, grasses, reeds, and sedges. Finally, the last
sixth comprehends the acotyledons or cryptogams—that is to say, plants
with flowers concealed or non-existent; fungi, mushrooms, mosses, algae,
* Charles Martins, Du Spitzberg au Sahara, p. 17.
| Title | The ocean, atmosphere, and life |
| Creator | Reclus, Elisée |
| Publisher | Harper |
| Place of Publication | New York |
| Date | 1873 |
| Language | eng |
| Type | Books/Pamphlets |
| Title | 00000396 |
| Type | Books/Pamphlets |
| Transcript | THE ASSEMBLAGE OF LIVING CREATURES. 357 nature of the animal and the plant; but on developing, they soon exhibit, by their structure and mode of life, the kingdom to which they belong. It is the vegetable kingdom in particular that peoples and embellishes our earth, thanks to the abundance of its species, the richness of its forms and colors, and the vast dimensions of its trees, some of which, like the Sequoia and the Eucalyptus, rise to more than three hundred feet high into the region of the clouds. But how does the planet produce the innumerable living bodies on its surface, from the green conferva, which germinates on ponds, to man, who, proud of his strength, bravely meets his destiny ? This is the great problem which excites the attention of the learned, and which is not, perhaps, altogether insoluble. The subject has given rise to much discussion, and to many experiments by chemists and biologists, without at present any definite result being arrived at. Botanists have not yet had time to count the prodigious number of plants which surround us, from the great oak, with spreading foliage, to the humble lichen, spread on the ground like a stain of blood. Besides, if the multitude ofthe vegetable species have not yet been computed, it must also be said that they are not yet agreed on the definition of species, some seeing simply varieties where others find absolutely distinct characters. A century ago, Linnaeus knew only 6000 species; the lists have since gradually increased in proportion as the various regions of the earth have been more and more explored, and now the total number of plants contained in the herbaria is estimated at about 12,000;* the increase has thus been, on an average, about a thousand each year. As to the numerous species which botanists have not yet classified, nor even discovered, we can only judge by proportion ofthe probable figure. It is thus that M. Alphonse de Candolle has been able to fix, in a general manner, the number of 400,000 to 500,000 species (250,000 being phanerogams) for the whole of the terrestrial flora. Up to our days, therefore, hardly a quarter of our riches has been recognized in the great inventory of the vegetable productions of the globe; and not a year passes without important discoveries being made by travelers in different parts of the world. Even the best known countries of Europe, which botanists have not ceased to explore for a century, present every year new species to fortunate collectors of plants. Of the number of classified species, already so considerable, the greatest part, or about two-thirds, is composed of dicotyledonous phanerogams— that is to say, of plants with visible flowers, and springing from the ground with at least two primordial leaves: these are the highest species of the vegetable series. Of the third which remains in the whole of terrestrial vegetation, about a half consists of monocotyledons—that is to say, of plants which have also apparent flowers, but which spring up with a single seed-leaf: such are palms, grasses, reeds, and sedges. Finally, the last sixth comprehends the acotyledons or cryptogams—that is to say, plants with flowers concealed or non-existent; fungi, mushrooms, mosses, algae, * Charles Martins, Du Spitzberg au Sahara, p. 17. |
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