2i6 Evolution and Distribution of Fishes 



country. The corresponding memoirs of W. von der Marck 

 (756': v: II, 22,31 ) for the Upper Cretaceous of West- 

 phalia; of Reuss (75^:98), Geinitz {160) and Fritsch 

 {161) for Bohemia demonstrated like conditions for central 

 Europe. Those of Bassani {162: 15), Davis (/65:457) 

 and Pictet {164) for Italy and Mt, Lebanon; of Leidy, 

 Cope, Williston, Stewart (/<^5:385), Loomis {166) and 

 others for the extensive Benton-Niobrara and related beds 

 in central North America, all prove widespread invasion of 

 the sea that was started almost wholly in late Jurassic times, 

 but became highly accentuated in the Upper Cretaceous 

 epoch. 



Such comparative distributional tables also as those 

 of A. S. Woodward for the strata of Lebanon and England 

 (7(57:471), and of A. S. Stewart (Op. supra) for the 

 Niobrara strata of Kansas, as compared with those of 

 European, West Asiatic, and other localities are most 

 instructive. Thus Dercetis is shown to be common to Mt. 

 Lebanon, to Wurtemberg, to England, and to the United 

 States. Sardinius is common to all of the above except 

 England; Spaniodon occurs in Mt. Lebanon and the United 

 States; while other equally striking distributional facts ap- 

 pear. Some of these are discussed, and a possible natural 

 explanation is given, in future chapters. So the presence 

 of marine invertebrate fossils, side by side with the skele- 

 tons, teeth, scales, or spines of teleost, pycnodont, cestraci- 

 ont, or selachian fishes, is now a common happening of 

 marine Cretaceous strata. 



But that even over the above areas, where heavy chalk 

 deposits had formed, an elevation of land might again give 

 rise to freshwater lakes, with their typical fossilized organ- 

 isms, has been shown clearly to have taken place. Thus over 

 extensive parts of central Europe marine deposits of Ceno- 

 manian age were succeeded by beds that locally are known 

 as "Pflanzen-Quader." These not only contain abundant 

 remains of elm, ash, laurel and other dicotyledonous trees, 

 but the flora has been so abundant as to give rise to carbon- 

 aceous shales, or to thin beds, or even thick beds of coal. 

 The absence of marine organisms among these remains 

 is sufficient proof that the sea had for the time retreated. 



