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Lyell, Charles, Sir, 1797-1875

"The Student's Elements of Geology"


After studying 300 specimens of these insects from the Lias, Mr. Westwood
declares that they comprise both wood-eating and herb-devouring beetles, of the
Linnean genera Elater, Carabus, etc., besides grasshoppers (Gryllus), and
detached wings of dragon-flies and may-flies, or insects referable to the
Linnean genera Libellula, Ephemera, Hemerobius, and Panorpa, in all belonging to
no less than twenty-four families. The size of the species is usually small, and
such as taken alone would imply a temperate climate; but many of the associated
organic remains of other classes must lead to a different conclusion.
FOSSIL PLANTS.
Among the vegetable remains of the Lias, several species of Zamia have been
found at Lyme Regis, and the remains of coniferous plants at Whitby. M. Ad.
Brongniart enumerates forty-seven liassic acrogens, most of them ferns; and
fifty gymnosperms, of which thirty-nine are cycads, and eleven conifers. Among
the cycads the predominance of Zamites, and among the ferns the numerous genera
with leaves having reticulated veins (as in Figure 349), are mentioned as
botanical characteristics of this era.


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