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Page:Popular Science Monthly Volume 57.djvu/436

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POPULAR SCIENCE MONTHLY.

the Callovian. More recent marine horizons have certainly not been formed at Cape Flora, as far as I can judge from the collection of fossils before me. . . . . The Oxfordian and all the more recent Jurassic horizons do not occur as marine deposits at Cape Flora."

He finds species pertaining to the Lower Bajocian, Lower, Middle and Upper Callovian horizons. It is most interesting to note that only one other part of the arctic regions, Prince Patrick Island, Parry Archipelago, has produced fossils, described by Haughton as Lias, that are certainly older than the Callovian. It is, however, recognized as possible that Lundgreen's fossils from East Greenland may form another exception.

Pompeckj points out that while the Bajocian fauna of Cape Flora is without analogy in the arctic regions, it nevertheless presents distinct affinities to the Central European Jura, and especially resembles the Russian Callovian.

Moreover, this Jurrassic collection from Cape Flora is of special importance in outlining the geographic distribution of that system. Pompeckj adds: "Hence the existence of a Bajocian sea in the north of the Eurasian Jura continent is proved beyond all doubt. . . . As early as the Bajocian period, there existed a Shetland Straits, which separated the Eurasian continent, existing through the Lias period until the end of the Bathonian, from the nearctic Jura continent."

The comments relative to the transition of Nova Zembla, Spitzbergen, Franz Josef Land, and possibly Alaska, from land to sea and sea to land, are of marked interest, indicating as they do that large areas of polar regions were exposed in the mesozoic period to repeated and very considerable oscillations of the sea level.

The more interesting of the Jurassic fossils, found at Cape Flora, are shown in the accompanying illustration. Cadocera Nanseni (n. sp.), 1, 2, 3, 5, 6. Cadoceras, sp. ex. aff. Cad. Nanseni (n. sp.), 4. Cadoceras Tchefkini, d'Orb, 7. Cadoceras, sp. indet., 8. Quenstedoceras vertumnum, Sintzow, 9. Cadoceras Frearsi, d'Orb, 10. Macrocephalites, 11. Macrocephalites Koettlitzi, n. sp., 12.

The collections of fossil plants, made by Nansen in Franz Josef Land through the courtesy of the Jackson-Harmsworth expedition, are of scientific value as indicating the fossil Jurassic flora of Franz Josef Land as compared with that of Spitzbergen. These collections fill in a not inconsiderable gap in the Arctic regions, and Nathorst's investigations serve to confirm the opinions and statements made by Professor Heer, whose five volumes of Flora Fossilis Arctica constitute a monumental work. As is well known, research has established the fact that at one time Spitzbergen was covered with a luxuriant miocene vegetation—cypresses, birches, sequoia?, oaks and planes. It moreover appears that tin's growth was coincident with the period when Spitzbergen. Green-