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have been found ; nor is this gap filled up by the conglomerates and coarse arenaceous beds which, as I have explained in “ Acadian Geology,” in some localities take the place of the limestones, as they do also in the Appalachian region farther south.

The palæobotanical and strategraphical equivalents of this series abroad would seem to be the following:

1. The Vespertine group of Rogers in Pennsylvania.
2. The Kinderhook group of Worthen in Illinois.
3. The Marshall group of Winchell in Michigan.
4. The Waverley sandstone (in part) of Ohio.
5. The Lower or False Coal-measures of Virginia.

6. The Calciferous sandstones of McLaren, or Tweedian group of Tate in Scotland.

7. The Lower Carboniferous slate and Coomhala grits of Jukes in Ireland.

8. The Culm and Culm Grauwacke of Germany.

9. The Graywacke or Lower Coal-measures of the Vosges, as described by Schimper.

10. The Older Coal-formation of the Ural, as described by Eichwald.

11. The so-called “ Ursa Stage” of Heer includes this, but he has united it with Devonian beds, so that the name cannot be used except for the local development of these beds at Bear Island, Spitzbergen. The Carboniferous plants of arctic America, Melville Island, &c., as well as those of Spitzbergen, appear all to be Lower Carboniferous.*

All of the above groups of rocks are characterised by the prevalence of Lepidodendra of the type of L. corrugatum, L. Veltheimianum, and L. Glincanum; pines of the sub-genus Pitus of Witham, Palæoxylon of Brongniart, and peculiar ferns of the genera Cyclopteris, Cardiopteris, Triphyllopteris, and Sphenopteris. In all the regions above referred to they form the natural base of the great Carboniferous system.

In Virginia, according to Fontaine and White, types, such as Archæopteris, which in the north are Upper Erian, occur in this group. Unless there have been some errors in fixing the lower limit of the Vespertine, this would indicate a longer continuance of old forms in the south.

* “Notes on Geological Map of the Northern Portion of the Dominion of Canada," by Dr. G. M. Dawson, 1887.

2. ERIAN FLORA. (1) Upper Erian Sub-Flora :

This corresponds to the Catskill and Chemung of the New York series, and to the Upper Devonian of Europe.

The flora of this formation, which consists mostly of sandstones, is not rich. Its most distinctive species on both sides of the Atlantic seem to be the ferns of the genus Archæopteris, along with species referred to the genus Cyclopteris, but which, in so far as their barren fronds are concerned, for the most part resemble Archæopteris.

The characteristic American species are Archæopteris Jacksoni, A. Rogersi, and A. Gaspiensis. Cyclopteris obtusa and C. (Platyphyllum) Browniï are also very characteristic species. In Europe, Archæopteris Hibernica is a prevalent species.

Leptophleum rhombicum and fragments of Psilophyton are also found in the Upper Erian. There is evidence of the existence of vast numbers of Rhizocarps in this period, in the deposits of sporecases (Sporangites Huronensis) in the shales of Kettle Point, Lake Huron; and in deposits of similar character in Ohio and elsewhere in the West.

The Upper Erian flora is thus very distinct from that of the Lower Carboniferous, and the unconformable relation of the beds in the Northeast may perhaps indicate a considerable lapse of time. Still, even in localities where there appears to be a transition from the Carboniferous into the Devonian, as in the Western States and in Ireland, the characteristic flora of each formation may be distinguished, though, as already stated, there is apparently some mixture in the South.

(2) Middle Erian Sub-Flora :

Both in Canada and the United States that part of the great Erian system which may be regarded as its middle division, the Hamilton and Marcellus shales of New York, the Cordaites shales of St. John, New Brunswick, and the middle shales and sandstones of the Gaspé series, presents conditions more favourable to the abundant growth of land-plants than either the upper or lower member. In the St. John beds, in particular, there is a rich fern flora, comparable with that of the coal-formation, and numerous stipes of ferns and trunks of tree-ferns have been found in the Hamilton and Corniferous series in the West, as well as trunks of Dadoxylon. It is, however, distinguished by a prevalence of small and delicate species, and by such forms as Hymenophyllites and the smaller Sphenopterids, and also by some peculiar ferns, as Archæopteris and Megalopteris. In addition to ferns, it has small Lepidodendra, of which L. Gaspianum is the chief. Calamiteæ occur, Archæocalamites radiatus being the dominant species. This plant, which in Europe appears to reach up into the Lower Carboniferous, is so far strictly Erian in northeast America. Sigillariæ scarcely appear, but Cordaites is abundant, and the earliest known species of Dadoxylon appear, while the Psilophyton, so characteristic of the Lower Erian, still continues, and the remarkable aquatic plants of the genus Ptilophyton are locally abundant.

(3) Lower Erian Sub-Flora :

This belongs to the Lower Devonian sandstones and shales, and is best seen in that formation at Gaspé and the Bay des Chaleurs. It is equivalent to the Oriskany sandstone, so far as its animal fossils and mineral character are concerned. It is characterised by the absence of true ferns, Calamites and Sigillariæ, and by the presence of such forms as Psilophyton, Arthrostigma, Leptophleum, and Nematophyton. Lepidodendron Gaspianum and Leptophleum already occur, though not nearly so abundant as Psilophyton.

The Lower Erian plants have an antique and generalised aspect which would lead us to infer that they are near the beginning of the land-flora, or perhaps in part belong to the close of an earlier flora still in great part unknown; and few indications of land-plants have been found earlier.

At Campbellton and Scaumenac Bay, on the Bay des Chaleurs, fossil fishes of genera characteristic of the Lower and Upper Devonian horizons respectively, occur in association with fossil plants of these horizons, and have been described by Mr. Whiteaves.*

It is interesting to note that, as Fontaine and White have observed, certain forms which are Erian in the northeast are found in the Lower members of the Carboniferous in West Virginia, indicating the southward march of species in these periods.

3. THE SILURIAN FLORA AND STILL EARLIER INDICATIONS OF

PLANTS.

In the upper beds of the Silurian, those of the Helderberg series, we still find Psilophyton and Nematophyton; but below these we know no land-plants in Canada. In the United States, Lesquereux and Claypole have described remains which may indicate the existence of lycopodiaceous and annularian types as far back as the be

*“Transactions of the Royal Society of Canada.”

ginning of the Upper Silurian, or even as low as the Hudson River group, and Hicks has found Nematophyton and Psilophyton in beds about as old in Wales, along with the uncertain stems named Berwynia. In the Lower Silurian the Protannularia of the Skiddaw series in England may represent a land-plant, but this is uncertain, and no similar species has been found in Canada.

The Cambrian rocks are so far barren of land-plants; the socalled Eophyton being evidently nothing but markings, probably produced by crustaceans and other aquatic animals. In the still older Laurentian the abundant beds of graphite probably indicate the existence of plants, but whether aquatic or terrestrial it is impossible to decide at present.

It would thus appear that our certain knowledge of land-vegetation begins with the Upper Silurian or the Silurio-Cambrian, and that its earliest forms were Acrogens allied to Lycopods, and prototypal trees, forerunners of the Acrogens or the gymnosperms. In the Lower Devonian little advance is made. In the Middle Devonian this meagre flora had been replaced by one rivalling that of the Carboniferous, and including pines, tree-ferns, and arboreal forms of Lycopods and of equisetaceous plants, as well as numerous herbaceous plants. At the close of the Erian the flora again became meagre, and continued so in the Lower Carboniferous. It again became rich and varied in the Middle Carboniferous, to decay in the succeeding Permian.

II.-HEER'S LATEST RESULTS IN THE GREENLAND

FLORA.

*

A VERY valuable report of Prof. Steenstrup, published in Copenhagen in 1883, the year in which Heer died, contains the results of his last work on the Greenland plants, and is so important that a summary of its contents will be interesting to all students of fossil botany or of the vicissitudes of climate which the earth has undergone.

The plant-bearing beds of Greenland are as follows, in ascending order:

1. CRETACEOUS. 1. The Komé series, of black shales resting on the Laurentian gneiss. These beds are found at various other localities, but the

* Meddelelser om Gronland, Hefte V., Copenhagen, 1883.

name above given is that by which they are generally knr vn. Their flora is limited to ferns, cycads, conifers, and a few endogens, with only Populus primæva to represent the dicotyledons. These beds are regarded as Lower Cretaceous (Urgonian), but the animal fossils would seem to give them a rather higher position. They may be regarded as equivalent to the Kootanie and Queen Charlotte beds in Canada, and the Potomac series in Virginia.

2. The Atané series. These also are black shales with darkcoloured sandstones. They are best exposed at Upernavik and Waigat. Here dicotyledonous leaves abound, amounting to ninety species, or more than half the whole number of species found. The fossil plants resemble those of the Dakota series of the United States and the Dunvegan series of Canada, and the animal fossils indicate the horizon of the Fort Pierre or its lower part. They may be regarded as representing the lower part of the Upper Cretaceous. The genera Populus, Myrica, Quercus, Ficus, Platanus, Sassafras, Laurus, Magnolia, and Liriodendron are among those represented in these beds, and the peculiar genera Macclintockia and Credneria are characteristic. The genus Pinus is represented by five species, Sequoia by five, and Salisburia by two, with three of the allied genus Baiera. There are many ferns and cycads.

3. The Patoot series. These are yellow and red shales, which seem to owe their colour to the spontaneous combustion of pyritous lignite, in the manner observed on the South Saskatchewan and the Mackenzie rivers. Their age is probably about that of the Fox-Hill group or Senonian, and the Upper Cretaceous of Vancouver Island, and they afford a large proportion of dicotyledonous leaves. The genera of dicotyledons are not dissimilar from those of Atané, but we now recognise Betula and Alnus, Comptonia, Planera, Sapotacites, Fraxinus, Viburnum, Cornus, Acer, Celastrus, Paliurus, Ceanothus, Zizyphus, and Cratægus as new genera of modern aspect.

On the whole there have been found in all these beds 335 species, belonging to 60 families, of which 36 are dicotyledonous, and represent all the leading types of arborescent dicotyledons of the temperate latitudes. The flora is a warm temperate one, with some remarkable mixtures of sub-tropical forms, among which perhaps the most remarkable are Kardocarpum referred to the Pandaneæ, and such exogens as Ficus and Cinnamomum.

2. TERTIARY. 4. The Unartok series. This is believed to be Eocene. It consists of sandstone, which appears on the shores of Disco Island, and

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