316 



HISTORICAL GEOLOGY 



are found. . . . Doubtless, at Oeningen, in Miocene times, there 

 was an extensive lake surrounded by dense forests, through which 

 ran a small river emptying into the lake ; and the Insects drowned 

 in its waters, and the leaves strewn by the winds on its surface, 

 were cast ashore by the waves. . . . Over 500 of the Oeningen 

 Insects were Beetles." l 



Another remarkable occurrence of fossil Insects is in the amber 

 of northern Germany, especially on the shores of the Baltic Sea, 

 where fully 2000 species have been obtained. The amber is a 



Fig. 196 



A nearly perfect fossil Teleost Fish, Diplomystus densatus, from the Eocene of 

 Wyoming. (After Veatch, U. S. Geological Survey, Prof. Paper 56.) 



fossil resin of early Oligocene age derived from certain Conifers. 

 The Insects were caught in the resin while it was still soft and 

 sticky and they were thus literally embalmed and perfectly pre- 

 served to the present day in the often quite transparent amber. 



At Florissant, Colorado, certain fresh water shales of Oligo- 

 cene (?) age are said to be black with the remains of Insects. Over 

 2000 species are represented as well as various plants, Fishes, and 

 even a Bird with well-preserved feathers. 



Fishes. — These were in general much like those of the later 

 Mesozoic, though even more modern in aspect. Teleosts (Fig. 196) 

 predominated, but Sharks were abundant and of great size — 60 

 to 80 feet long — with fossil teeth up to 5 or 6 inches long occur- 



1 J. Le Conte: Elements of Geology, 5th ed., p. 534. 



