In Carboniferous and Permian Epochs 165 



mian, as compared with their luxuriance during the Coal 

 Measure period, throughout Europe. One was the wide- 

 spread extrusion of igneous rocks as beds of lava, tuff and 

 dust, or the injection of volcanic material into the older 

 stratified rocks as extensive dykes. Such must often have 

 caused a wholesale destruction of plant and animal life over 

 many thousands of square miles of country. 



Another and remarkable change that seems to have 

 become more and more pronounced during deposition of 

 the Lower Permian was the initiation of a well-marked 

 glacial period. In Europe conglomerate beds occur that 

 seem only explicable as glacial clay and boulder formations. 

 But it is in the Southern Hemisphere, from South East 

 Africa to India and Australia, that the most pronounced 

 examples of glacial phenomena are testified to by the 

 rocks. It is not surprising, therefore, that while the lower 

 part of the Lower Permian (Rothliegende) shows marked 

 resemblances to the Upper part of the Carboniferous, the 

 Upper Permian shows transition toward the later or Tri- 

 assic system. 



The uppermost zone of the Permian is the Kupfer- 

 schiefer (copper-slate) which, equally in Europe and in 

 Texas, shows one or more clay-beds, that are rich in copper 

 ore. This is the zone also that is usually richest in fresh- 

 water or land fossils, and whose contents have been most 

 fully examined. 



The accounts alike of Geinitz and of Fritsch testify 

 to the presence of an abundant freshwater-land flora and 

 fauna, while the numerous wide stretches of rocks that 

 show mud layers with rain-pits or sun-cracks, or of shaly 

 sandstones with tracks of amphibians and shore ripple- 

 ridges, suggest that dry hot conditions at one time, no 

 less than glacial climatic states at another, were typical. 

 But that the flora was often abundant and varied is proved 

 by the thick coal beds found in the Lower Permian of 

 France, East Germany, and West Russia, as well as in 

 India, Australia and South Africa. 



The freshwater and land fauna preserved to us consist 

 of numerous insects, myriapods, estheriae, and specially 



