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latter have long ago descended from their pristine eminence to a very humble place in nature, the former still, in the southern hemisphere at least, retain their arboreal
dimensions and anB
The family of the Equisetacece, or mare’s-tails, was also represented by large species of Calamites and by Asterophyllites in the Erian;
but, as its headquarС
ters are in the Car
boniferous, we may DI
defer its considera
tion till the next D
chapter. (Figs. 27, 28.)
Passing over these for the present, we find that the flowering plants are repre
sented in the Erian Fig. 28.--Asterophyllites (Erian, New Bruns- forests by at least
wick). A, Asterophyllites latifolia. B, Do., apex of stem (?) fruit. c, ç, A. scutigera.
two types of GymD, A. latifolia, larger whorl of leaves. Di, Leaf.
nosperms, that of
Taxinece or yews, and an extinct family, that of the Cordaites (Figs. 30, 31). The yew-trees are closely allied to the pines and spruces, and are often included with them in the family of Coniferoe. They differ, however, in the habit of producing berries or drupe-like fruits instead of cones, and there is some reason to believe that this was the habit of the Erian trees of this group, though their wood in some instances resembles rather that of the Araucaria, or Norfolk Island pine, than that of the modern yews. These trees are chiefly known to us by their mineralised trunks, which are often found like drift-wood on modern sandbanks embedded in the Erian sandstones or limestones. It often shows its structure in the most perfect manner in specimens penetrated by calcite or silica, or by pyrite, and in which the original woody matter has
FIG. 29.- Dadoxylon Quangondianum, an Erian conifer, A, Fragment
showing Sternbergia pith and wood; a, medullary sheath; b, pith ; Ç, wood; dų section of pith. B, Wood-cell; a, hexagonal areole; b, pore. o, Longitudinal section of wood, showing, a, areolation, and b, medullary rays. D, Transverse section, showing, a, wood-cells, and b, limit of layer of growth. (B, C, D, highly magnified.)
been resolved into anthracite or even into graphite. These trees have true woody tissues presenting that beautiful arrangement of pores or thin parts enclosed in cuplike discs, which is characteristic of the coniferous trees, and which is a great improvement on the barred tissue already referred to, affording a far more strong, tough, and durable wood, such as we have in our modern pines and yews (Fig. 29).
These primitive pines make their appearance in the Middle Erian, in various parts of America, as well as in Scotland and Germany, and they are represented by wood indicating the presence of several species. I have myself indicated and described five species from the Erian of Canada and the United States. From the fact that these trees are represented by drifted trunks embedded in sandstones and marine limestones, we may, perhaps, infer that they grew on the rising grounds of the Erian land, and that their trunks were carried by river-floods into the sea. No instance has yet certainly occurred of the discovery of their foliage or fruit, though there are some fan-shaped leaves usually regarded as ferns which may have belonged to such trees. These in that case would have resembled the modern Gingko of China, and some of the fruits referred to the genus Cardiocarpum may have been produced by them. Various names have been given to these trees. I have preferred that given by Unger, Dadoxylon, as being more non-committal as to affinities than the others.* Many of these trees had very long internal pith-cylinders, with curious transverse tubulæ, and which, when preserved separately, have been named Sternbergia.
Allied to these trees, and perhaps intermediate between them and the Cycads, were those known as Cordaites (Fig. 30), which had trunks resembling those of Dadoxylon, but with still larger Sternbergia piths and an internal axis of scalariform vessels, surrounded by a comparatively thin woody cylinder. Some of them have leaves over a foot in length, reminding one of the leaves of broad-leaved grasses or iridaceous plants. Yet their flowers and fruit seem to have been more nearly allied to the
than to any other plants (Fig. 31). Their stems were less woody
* Araucarites, Goeppert; Araucariozylon, Kraus.
and their piths larger than in the true pines, and some of the larger-leaved species must have had thick, stiff branches. They are regarded as constituting a separate family, intermediate between pines and cycads, and, be
FIG. 30.—Cordaites Robbii (Erian, New Brunswick). a, Group of young
leaves. b, Point of leaf. c, Base of leaf. d, Venation, magnified.
ginning in the Middle Devonian, they terminate in the Permian, where, however, some of the most gigantic species occur. In so far as the form and structure of the leaves, stems, and fruit are concerned, there is marvellously little difference between the species found in the
Erian and the Permian. They culminated, however, in the Carboniferous period, and the coal-fields of southern France have proved so far the richest in their remains.
Lastly, a single specimen, collected by Prof. James Hall, of Albany, at Eighteen-mile Creek, Lake Erie, has the structure of an ordinary angiospermous exogen, and has been described by me as Syringoxylon mirabile. *
FIG. 31.-Erian fruits, &c., some gymnospermous, and probably of Cordaites
and Taxine trees (St. John, New Brunswick). A, Cardiocarpum cornutum. B, Cardiocarpum acutum. O, Cardiocarpum Crampii. D, Cardiocarpum Baileyi. E, Trigonocarpum racemosum. E, ES, Fruits enlarged. F, Antholithes Devonicus. Q, Annularia acuminata. H, Asterophyllites acicularis. #%, Fruit of the same. K, Cardiocarpum (? young of A.). 1, Pinnularia dispalans (probably á root).
This unique example is sufficient to establish the fact of the existence of such plants at this early date, unless some accident may have carried a specimen from a later forma