The Story of a Piece of Coal | Page 5

the
various kinds of plants. We shall then doubtless find it far easier
thoroughly to understand the position in the scale of organisation to
which the coal plants are referable.
[Illustration: FIG. 9.--Asterophyllites foliosa. Coal-measures.]
The plants which are lowest in organisation are known as Cellular.
They are almost entirely composed of numerous cells built up one
above the other, and possess none of the higher forms of tissue and
organisation which are met with elsewhere. This division includes the

lichens, sea-weeds, confervae (green aquatic scum), fungi (mushrooms,
dry-rot), &c.
The division of Vascular plants includes the far larger proportion of
vegetation, both living and fossil, and these plants are built up of
vessels and tissues of various shapes and character.
All plants are divided into (1) Cryptogams, or Flowerless, such as
mosses, ferns, equisetums, and (2) Phanerogams, or Flowering.
Flowering plants are again divided into those with naked seeds, as the
conifers and cycads (gymnosperms), and those whose seeds are
enclosed in vessels, or ovaries (angiosperms).
Angiosperms are again divided into the monocotyledons, as the palms,
and dicotyledons, which include most European trees.
Thus:--

------------------------------------------------
-------------------
| (M.A. Brongniart). |
|(Lindley). |
|CELLULAR |
| |
| Cryptogams (Flowerless) |Fungi, seaweeds,
|Thallogens |
| | lichens
| |
| | |
|
|VASCULAR |
| |
| Cryptogams (Flowerless) |Ferns, equisetums,
|Acrogens |
| | mosses,
lycopodiums| |
| Phanerogams (Flowering) | |
|
| Gymnosperms (having |Conifers and
|Gymnogens |
| naked seeds) | cycads
| |
| Two or more Cotyledons |
| |

| Angiosperms (having |
| |
| enclosed seeds) |