FOSSIL FLORAS OF AECTIC REGIONS — NATHORST. 343 



show that we have here to deal with fresh-water deposits. M. Ostrup's * 

 microscopic examination of the diatoms, found in the same beds as 

 the fossil plants, confirms this conclusion, for they are fresh-water 

 species. 



Among the beds furnishing Tertiary plants, so abundant in Green- 

 land, I will only mention those of Haron (Hare Island), near 

 Waigattet. Here the plants occur either in a true basaltic tuff, or 

 in an altered tufa or a sediment formed from it, which is overlain 

 with basalts. 



The investigation of two beds, which I made in 1883, has proved 

 that they can not be other than formations laid down above sea level. 

 In one of these deposits the fossil flora consisted almost exclusively of 

 leaves of the maple (Acer), crowded like those which cover the ground 

 in autumn, and among these leaves large samaras, like those of 

 A. otopteryx Gp., occur. In another bed the tuff was formed of 

 cinders and small lapilli, and the way in which the vegetable 

 fragments were inbedded leads one to suppose that the branches, 

 leaves, and fruits of the trees were broken off by a shower of cinders 

 and lapilli. A medley of silicified branches of different sizes occurs, 

 and among them are the cones of the spruce, the nuts of the walnut 

 (Juglans), and the hickory (Carya), with the leaves of Ginkgo, etc. 

 In the finer tuffs we likewise find the leaves of the walnut, the leaves 

 and fruits of an ash (Fraxinus macrophylla Hr.), and the leaves of 

 species common in the Tertiary flora of Greenland, such as the plane, 

 oak, chestnut, beech, etc. 



The presence of the leaves of Potamogeton, associated with a fresh- 

 water mussel (TJnio), indicates that the 'deports were bi fresh-water 

 origin. Some of the branches of tfte trees are silicmed and Exhibit, 

 under the microscope, an extremely well-preserved structure. Dr. 

 J. Schuster, who has undertaken a preliminary examination of these 

 remains, concludes that they all belong to one species, "wm*cK was 

 probably either an arborescent member of the legumJmvese or of the 

 rosacea?. It is clear that we have here to deal with' fragments of 

 vegetation broken off by a shower of ashes and entombed in them, 

 though some fragments may have been transported into a fresh-water 

 basin containing mussels and aquatic plants. 



The Tertiary plants discovered by the Norwegian expedition to 

 Ellesmere Land deserve special mention on account of their state of 

 preservation. They consist almost entirely of branches of Sequoia 

 Langsdorfii, contained in a bituminous laminated clay, from which 

 I have been able to remove them by a process of washing, with 

 the result that they are now isolated like dried specimens in a 

 herbarium. 



1 E. Ostrup, "Diatomderne i nogle islandske Surtarbrandlag," pt. 1: Meddel. fra Dausls Geol. Forening, 

 No. 3; Copenhagen, 1S9G. Pt. 2, ibid., No. G, 1900. 



