218 GEOLOGY. 



looking beds of the Paris basin. Since it is often thick, as well as wide- 

 spread (it locally attains a thickness of several thousand feet), the sea 



must have swarmed with foraminifera. 

 Hardly anywhere else in the rocks of the 

 whole earth are there indications of such 

 great numbers of organisms of one type. 

 The Hippurite limestone of the Cretaceous, 

 and the Fusulina limestone of the Carbon- 

 iferous, are perhaps most nearly compar- 



, . „ ,. . able. Fossil nummulites are also found in 



Fig. 426. — A bit of nummuhtic ... 



limestone. the sandstones, and even in the iron ores 



of the period. 



In the northern Alps and Carpathians, there is a series of clastic 

 beds known as the Flysch. The lower portion of the series is believed 

 to be Cretaceous, but in Bavaria the upper portion is associated with 

 nummulitic limestone, and is therefore thought to be Eocene. The 

 peculiarity of this formation is the occurrence within it of gigantic 

 bowlders, some of which are said to have a diameter of 100 feet. They 

 occur singly or in groups, and are sometimes embedded in clay, though 

 more commonly they are a constituent of conglomerate. Some of the 

 bowlders are foreign to the adjacent mountains, and have been thought 

 to suggest the existence of glaciers. The paucity of fossils is in harmony 

 with this suggestion, without proving its truth. If this inference be 

 correct, it would seem that there must have been high mountains in 

 central Europe, for a low temperature does not appear to have affected 

 any considerable area of the sea. From high mountains, glaciers might 

 have descended to low levels, as in New Zealand to-day, where between 

 latitude 43° and 44° S., glaciers descend to within 500 feet of the sea- 

 level, and deposit their moraines in a region of tree ferns and palms. 1 



Against this interpretation much may be said. At any rate the 

 fossils of the period in the surrounding regions denote a climate too 

 warm to allow the hypothesis to be accepted, except on the basis of irre- 

 futable evidence. Similar problems are presented by certain formations 

 of other periods. In the North Tyrol, the Eocene contains coal. Igneous 

 rocks of Eocene age are common in Europe as in America. 



Some idea of the deformative movements which have taken place since 



1 James Geikie. Outlines of Geology. 



