LOWER MIOCENE, BELGIUM. 
241 
ent, while an addition of 10° to the mean temperature of 
Central Europe would probably be as much as was required. 
The chief locality where this wonderful flora is preserved is 
at Atanekerdluk in North Greenland (lat. 70°), on a hill at an 
elevation of about 1200 feet above the sea. There is here a 
considerable succession of sedimentary strata pierced by vol¬ 
canic rocks. Fossil plants occur in all the beds, and the erect 
trunks as thick as a man’s body which are sometimes found, 
together with the abundance of specimens of flowers and 
fruit in good preservation, sufficiently prove that the plants 
grew where they are now found. At Disco island and other 
localities on the same part of the coast, good coal is abun¬ 
dant, interstratified with beds of sandstone, in some of which 
fossil plants have also been found, similar to those at Atan¬ 
ekerdluk. 
Lower Miocene, Belgium. —The Upper Miocene Bolderberg 
beds, mentioned at p. 224, rest on a Lower Miocene forma¬ 
tion called the Rupelian of Dumont. This formation is best 
seen at the villages of Rupelmonde and Boom, ten miles south 
of Antwerp, on the banks of the Scheldt and near the junc¬ 
tion with it of a small stream called the Rupel. A stiff* clay 
abounding in fossils is extensively worked at the above lo¬ 
calities for making tiles. It attains a thickness of about 100 
feet, and though very different in age, much resembles in 
mineral character the ‘‘ London clay,” containing, like it, sep- 
taria or concretions of argillaceous limestone traversed by 
cracks in the interior, which are filled with calc-sj^ar. The 
shells, referable to about forty species, have been described 
by MM. Nyst and De Koninck. Among th^mLeda (or Nii- 
cula) Deshayesiana 
(see Fig. 156) is by 
far the most abun¬ 
dant; a fossil un¬ 
known as yet in the 
English tertiary 
strata, but when 
young much resem¬ 
bling Leda amygdaloides of the London Clay proper (see 
Fig. 213, p. 266). Among other characteristic shells are 
Pecten Hoenmghausii^ and a species of Cassidaria^ and sev¬ 
eral of the genus Pleurotoma, Not a few of these testacea 
agree with English Eocene species, such as Actceon simulatus^ 
Sow., Gancellaria emdsa^ Brander, Corbida pisum (Fig. 157), 
and Nautilus [Aturia) ziczac. They are accompanied by 
many teeth of sharks, as Lamna eontortidenSj Ag., Oxyrhi- 
naxiphodoUj Ag., Garcharodon angustidens (see Figure 196, 
11 
Leda (Nucula) Deshayesianaj Nyst. 
