FOSSIL FLORAS OF ARCTIC REGIONS — NATHORST. 341 



In relation to the present problems, the Tertiary floras are un- 

 doubtedly the most important, and for this reason I will enter into 

 the subject in some detail. But the materials are so wonderfully rich 

 that I shall have to restrict myself to giving some examples indicating 

 the nature of the beds containing the Tertiary plants in Spitsbergen, 

 Iceland, and Greenland. More especially, I shall recall that they are 

 found at 79° of north latitude in Spitsbergen; on the east coast of 

 Greenland between 74° and 75°, and on the west coast between 69° 

 and 73°; at Lady Franklin Bay, in Grinnell Land (81° 42"); in 

 Ellesmere Land between 77° and 78°; on the River Mackenzie at 65°; 

 in Alaska south of 60° (and therefore outside the Polar Circle); and, 

 lastly, in the islands of New Siberia (75°). Iceland, it is true, is 

 outside the Polar Circle, but nevertheless its Tertiary flora may be 

 included in this consideration. 



The Tertiary formations of Spitsbergen, which have a thickness of 

 perhaps 1,200 meters or thereabout, contain fossil plants and seams 

 of coal, both in the upper and lower beds, though the middle portion 

 is marine. As an example of the deposits with fossil plants from the 

 base of this formation the shales called the "Taxodium Shales," at 

 Cape Staratschin, may be mentioned. These are fine-grained black 

 soft shales, which form the roof of a small bed of coal. In the shales 

 the leafy branches, the flowers, the seeds, and the ovuliferous scales 

 of the Swamp Cypress (Taxodium distichum miocenum), the leafy 

 branches of Sequoia Nordenshioldi Hr., and Librocedrus Sabiniana 

 Hr., are particularly common. There are also associated a large 

 number of remains of graminese, cyperaceae, several species of pines 

 and firs, a Potamogeton, and the leaves of various dicotyledonous trees. 

 Thus, as Heer has shown, one is dealing here with fresh-water 

 sediments, in the neighborhood of which it is evident that the 

 swamp cypresses have formed forests, as in the swamps in the 

 southern portion of the United States to-day. This conclusion is also 

 confirmed by the occurrence of the remains of rather numerous insects, 

 among which there are a score of coleopterids, two of which are 

 hydrophilous coleopterids (Hydrobius and Laccophilus) . 



These beds with fossil plants, at the base of the Tertiary formations 

 of Spitsbergen, are overlain by thick marine sediments. In their 

 upper portion the latter show indications of a retreat of the ocean 

 and a recurrence of fresh-water conditions. It is possible that the 

 leaves found in the lower part of the higher horizon containing fossil 

 plants have been transported from afar by a river, and deposited near 

 its mouth, but as regards the upper portion deposition must have taken 

 place in vast swamps, on which the majority of the plants actually 

 lived. In these beds one notices thin seams of coal, a rreat 

 quantity of leafy branches, and also cones of Sequoia Langsdorfii 



