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It is the normal building, a house on bastions, both well and solidly made of stone and lime. Amongst the materials I found a fine yellow sandstone-grit and a nummulite so weathered that the shells stood out in strong relief. Both were new to us on this trap-coast, and no one could say where they were quarried; many thought they must have come from Europe, others that they are brought from inland.
Separate groups of strata are often characterised by distinct species of nummulite; thus the beds between the lower Miocene and the lower Eocene may be divided into three sections, distinguished by three different species of nummulites, N. variolaria in the upper, N. laevigata in the middle, and N. planulata in the lower beds.
Higher in the series is a remarkable calcareous rock, formerly called "the nummulite limestone," from the great number of discoid bodies resembling nummulites which it contains, fossils now referred by A. d'Orbigny to the genus Orbitoides, which has been demonstrated by Dr. Carpenter to belong to the foraminifera.
Dawson of Montreal, who detected in it, by aid of the microscope, the distinct structure of a Rhizopod or Foraminifer. Dr. Carpenter and Professor T. Rupert Jones have since confirmed this opinion, comparing the structure to that of the well-known nummulite. It appears to have grown one layer over another, and to have formed reefs of limestone as do the living coral-building polyp animals.
Middle Eocene, Bracklesham Bay. a. Natural size. b. Certain foraminifera called Nummulites begin, when we study the Tertiary formations in a descending order, to make their first appearance in these beds. Bracklesham. Dixon's Fossils of Sussex, Plate 8. a. Section of nummulite. b.
The opinion of many observers, that the Nummulitic formation belongs partly to the cretaceous era, seems chiefly to have arisen from confounding an allied genus, Orbitoides, with the true Nummulite.
Here and there, at Carmel and Gerizim, patches of the tertiary nummulite of Egypt make their appearance, and in the plains of Megiddo and the coast, as well as in the "Ghor" or valley of the Jordan, there is rich alluvial soil.
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