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Updated: June 23, 2025
It may be said that the Carboniferous formations demonstrate the existence of a vast extent of dry land in the present dry-land area, and that the supposed terrestrial Palaeozoic Vertebrate Fauna ought to have left its remains in the Coal-measures, especially as there is now reason to believe that much of the coal was formed by the accumulation of spores and sporangia on dry land.
It is an obvious example of systematic atavism, occurring suddenly and with the full development of all the qualities needed for the normal production of sporangia and spores. All of these must be concealed in a latent condition within the young tissues of the green stems.
But this resinous matter, which lies in the walls of the spores and sporangia, is a substance not easily altered by air and water, and hence tends to preserve these bodies, just as the bituminized cerecloth preserves an Egyptian mummy; while, on the other hand, the merely woody stem and leaves tend to rot, as fast as the wood of the mummy's coffin has rotted.
But, in their essential structure, they very closely resemble the earliest Lepidodendroid trees of the coal: their stems and leaves are similar; so are their cones; and no less like are the sporangia and spores; while even in their size, the spores of the Lepidodendron and those of the existing Lycopodium, or club-moss, very closely approach one another.
But if two sporangia are observed with their bases coherent without intermediary filaments of mycelium, it seems to me probable that the reproduction has taken place through the union, which happens in the following manner: Two filaments of mycelium become juxtaposed; after which the filaments of mycelium disappear in the sporangia newly formed, which by this same metamorphosis are deprived of the faculty of reproducing themselves through the filaments of myclium of which they are deprived.
One stellate compound plant hair, one Gemiasma verdans, two pollen. Grass flower dew. Some large white sporangia filled with spores. Grass blade dew, not anything of account. One pale Gemiasma, three blue Gemiasmas, Cosmarium, Closterium. Diatoms, pollen, found in greenish earth and wet with the dew. Remarks: Observations made at the pool with clinical microscope, one-quarter inch objective.
A, Goblet inverted over a saucer; B, filled with water; C, D, specimen of earth with ague plants. Observation 6. Some Gemiasma verdaus; good specimens, but scanty. Innumerable mobile spores. Dried. Observation 7. Red dust on gray soil. Innumerable mobile spores. Dried red sporangia of G. rubra. Observation 8. White incrustation. Innumerable mobile spores. No plants. Observation 9.
It may be said that the Carboniferous formations demonstrate the existence of a vast extent of dry land in the present dry-land area, and that the supposed terrestrial Palaeozoic Vertebrate Fauna ought to have left its remains in the Coal-measures, especially as there is now reason to believe that much of the coal was formed by the accumulation of spores and sporangia on dry land.
Reproduced by division and by resting spores produced in sporangia formed after the conjugation of two cells and union of their contents, and by zoospores formed in the vegetative cells or in the germinating resting spores. Diatomaceae. Multiplied by division and by the formation of new larger individuals out of the contents of individual conjugated cells; perhaps also by spores and zoospores.
But this resinous matter, which lies in the walls of the spores and sporangia, is a substance not easily altered by air and water, and hence tends to preserve these bodies, just as the bituminized cerecloth preserves an Egyptian mummy; while, on the other hand, the merely woody stem and leaves tend to rot, as fast as the wood of the mummy's coffin has rotted.
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