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a height of 5,000 to 7,000 feet above sea level, and are much sought after by tourists as one of the wonders of the country. Reports came to Europe concerning the largest of them which were quite fabulous, but we have received accurate accounts of them from Prof. Whitney. The tallest tree measured by him has a height of 325 feet, and in the case of one of the trees the number of the rings of growth indicated an age of about 1,300 years. It had a girth of 50 to 60 feet.

We know only two living species of Sequoia, both of which are confined to California. The one (S. sempervirens) is clothed with erect leaves, arranged in two rows, very much like our yew-tree, and bears small, round cones; the other (S. gigantea) has smaller leaves, set closely against the branches, giving the tree more the appearance of the cypress. The cones are egg-shaped, and much larger. These two types are therefore sharply defined.

Both of these trees have an interesting history. If we go back into the Tertiary, this same genus meets us with a long array of species. Two of these species correspond to those living at present: the S. Langsdorfii to the S. sempervirens, and the S. Couttsic to the S. gigantea. * But, while the living species are confined to California, in the Tertiary they are spread over several quarters of the globe.

Let us first consider the Sequoia Langsdorfii. This was first discovered in the lignite of Wetterau, and was described as Taxites langsdorfii. Heer found it in the upper Rhone district, and there lay beside the twigs the remains of a cone, which showed that the Taxites Langsdorfii of Brongniart belonged to the Californian genus Sequoia established by Endlicher. He afterward

* S. Couttsice has leaves like S. gigantea, and cones like those of S. sempervirens.

found much better preserved cones, together with seeds, along with the plants of east Greenland, which fully confirmed the determination. At Atanekerdluk in Greenland (about 70° north latitude) this tree is very common. The leaves, and also the flowers and numerous cones, leave no doubt that it stands very near to the modern redwood. It differs from it, however, in having a much larger number of scales in the cone. The tree is also found in Spitzbergen at nearly 78° north latitude, where Nordenskiöld has collected, at Cape Lyell, wonderfully preserved branches. From this high latitude the species can be followed down through the whole of Europe as far as the middle of Italy (at Senegaglia, Gulf of Spezia). In Asia, also, we can follow it to the steppes of Kirghisen, to Possiet, and to the coast of the Sea of Japan, and across to Alaska and Sitka. It is recognized by Mr. Starkie Gardner as one of the species found in the Eocene of Mull in the Hebrides. * It is thus known in Europe, Asia, and America, from 43° to 78° north latitude, while its most nearly related living species, perhaps even descended from it, is now confined to California.

With this S. Langsdorfii, three other Tertiary species are nearly related (S. brevifolia, Hr., S. disticha, Hr., and S. Nordenskiöldi, Hr.). These have been met with in Greenland and Spitzbergen, and one of them has lately been found in the United States. Three other species, in addition to these, have been described by Lesquereux, which appear to belong to the group of the S. Langsdorfii, viz., s. longifolia, Lesq., S. angustifolia, and S. acuminata, Lesq. Several species also occur in the Cretaceous and Eocene of Canada.

These species thus answer to the living Sequoia sempervirens ; but we can also point to Tertiary represen

* It is Fareites Campbelli of Forbes.

tatives of the S. gigantea. Their leaves are stiff and sharp-pointed, are thinly set round the branches, and lie forward in the same way: the egg-shaped cones are in some cases similar.

There are, however, in the early Tertiary six species, which fill up the gap between S. sempervirens and S. gigantea. They are the S. Couttsiæ, S. affinis, Lesq., S. imbricata, Hr., S. sibirica, Hr., S. Heerii, Lesq., and S. biformis, Lesq. Of these, S. Couttsic, Hr., is the most common and most important species. It has short leaves, lying along the branch, like S. gigantea, and small, round cones, like S. Langsdorfii and sempervirens. Bovey Tracey in Devonshire has afforded splendid specimens of cones, seeds, and twigs, which have been described in the “ Philosophical Transactions.” More lately, Count Saporta has described specimens of cones and twigs from Armissan. Specimens of this species have also been found in the older Tertiary of Greenland, so that it must have had a wide range. It is very like to the American S. affinis, Lesq.

In the Tertiary there have been already found fourteen well-marked species, which thus include representatives of the two living types, S. sempervirens and S. gigantea.

We can follow this genus still further back. If we go back to the Cretaceous age, we find ten species, of which five occur in the Urgon of the Lower Cretaceous, two in the Middle, and three in the Upper Cretaceous. Among these, the Lower Cretaceous exhibits the two types of the Sequoia sempervirens and S. gigantea. To the former the S. Smithiana answers, and to the latter, the Reichenbachii, Gein. The S. Smithiana stands indeed uncommonly near the S. Langsdorfii, both in the appearance of the leaves on the twigs and in the shape of the cones. These are, however, smaller, and the leaves do not become narrower toward the base. The S. pectina, Hr., of the Upper Cretaceous, has its leaves arranged in two rows, and presents a similar appearance. The S. Reichenbachii is a type more distinct from those now living and those in the Tertiary. It has indeed stiff, pointed leaves, lying forward, but they are arcuate, and the cones are smaller. This tree has been known for a long time, and it serves in the Cretaceous as a guiding star, which we can follow from the Urgonian of the Lower Cretaceous up to the Cenomanian. It is known in France, Belgium, Bohemia, Saxony, Greenland, and Spitzbergen (also in Canada and the United States). It has been placed in another genus -Geinitzia—but we can recognise, by the help of the cones, that it belongs to Sequoia.

Below this, there is found in Greenland a nearly related species, the S. ambigua, Hr., of which the leaves are shorter and broader, and the cones round and somewhat smaller.

The connecting link between S. Smithiana and Reichenbachië is formed by S. subuluta, Hr., and S. rigida, Hr., and three species (S. gracilis, Hr., S. fastigiata and S. Gardneriana, Carr.), with leaves lying closely along the branch, and which come very near to the Tertiary species S. Couttsiæ. We have therefore in the Cretaceous quite an array of species, which fill up the gap between the S. sempervirens and gigantea, and show us that the genus Sequoia had already attained a great development in the Cretaceous. This was still greater in the Tertiary, in which it also reached its maximum of geographical distribution. Into the present world the two extremes of the genus have alone continued; the numerous species forming its main body have fallen out in the Tertiary.

If we look still further back, we find in the Jura a great number of conifers, and, among them, we meet in the genus Pinus with a type which is highly developed, and which still survives ; but for Sequoia we have till now looked in vain, so that for the present we can not place the rise of the genus lower than the Urgonian of the Cres taceous, however remarkable we may think it that in that period it should have developed into so many species; and it is still more surprising that two species already make their appearance which approach so near to the living Sequoia sempervirens and S. gigantea.

Altogether, we have become acquainted, up to the present time, with twenty-six species of Sequoia. Fourteen of these species are found in the Arctic zone, and have been described and figured in the “Fossil Flora of the Arctic Regions.” Sequoia has been recognised by Ettingshausen even in Australia, but there in the Eocene.

This is, perhaps, the most remarkable record in the whole history of vegetation. The Sequoias are the giants of the conifers, the grandest representatives of the family, and the fact that, after spreading over the whole northern hemisphere and attaining to more than twenty specific forms, their decaying remnant should now be confined to one limited region in western America and to two species constitutes a sad memento of departed greatness.* The small remnant of S. gigantea still, however, towers above all competitors, as eminently the “big trees”; but, had they and the allied species failed to escape the Tertiary continental submergences and the disasters of the glacial period, this grand genus would have been to us an extinct type. In like manner the survival of the single gingko of eastern Asia alone enables us to understand that great series of taxine trees with fern-like leaves of which it is the sole representative.

Besides these peculiar and now rare forms, we have in the Mesozoic many others related closely to existing yews, cypresses, pines, and spruces, so that the conifers were probably in greater abundance and variety than they are at this day.

* The writer has shown that much of the material of the great lignite beds of the Canadian Northwest consists of wood of Sequoia of both the modern types.

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