OIANT FOSSIL SHARK I I I 



Other specimens shown in the hall include the smaller carnivorous 

 dinosaurs, the horned dinosaurs with, in one instance al least, a skull 

 seven feel in length, and ancient birds possessed of teel h. There is also a 

 fine collection of the very ancient reptiles of the Permian period, mostly 



from Texas and South Africa. Among them are the finback lizards, 

 Diadectes, a reptile with a solid-honed skull, and Eryops, a primitive 

 amphibian. The finest collection of fossil turtles in the world will be 

 found on the south side of the hall. 



In the Tower of the Southeast Pavilion are displayed the fossil fishes 

 which belong to a much earlier period than the mammals and reptile-. 

 Fossil Fishes some °^ theni having lived twenty to fifty millions of 

 years ago. Many of these forerunners of backboned 

 animals are quite unlike any living fishes and are probably only 

 very indirectly related to them; some were small, curiously encased in 

 shells; others, shown in the three cases in front of the visitor, attained 

 large size and were evidently formidable creatures. One of them, in 

 fact, Dinichthys, shown in the middle of the gallery, was probably 

 among the most destructive creatures that ever lived in the sea. Its 

 jaws were so strong that it could crush a plate of bone as thick as one's 

 hand. Such an actual specimen, fractured in life and showing the 

 marks of "teeth," is shown in a neighboring case. 



The collection is so arranged that he who makes the tour can see the 

 principal kinds of fossil fishes and is able, in a measure, to outline the 

 history and pedigree of the entire group. He can trace the rise and fall 

 of the early plate-covered fishes; the era of the sharks which on the one 

 hand supplanted the earliest fishes and were in time replaced by the more 

 efficient lungfishes and ganoids; the age of ganoids when the waters were 

 filled with these enamel-scaled fishes; finally the age of the bony-fishes, 

 or teleosts, the multitudinous forms of to-day, the herrings, cods, perches, 

 whose methods of swimming, feeding and breeding are far more efficient 

 than those of any of their predecessors. 



Above the entrance are the jaws, "models," spreading nine feet, of a 

 huge fossil shark in which the actual teeth are arranged as in the sharks 

 Jaws of of to-day, in the usual banks or row^s — the teeth in the 



Giant Fossil hinder rows serving to replace those in front, nature 

 Shark having dealt more kindly in the matter of teeth with 



sharks than with man. Such a shark probably measured from seventy 

 to ninety feet and its race may well have become extinct, when for 

 various reasons the enormous volume of food necessary to support it 

 could not be maintained within its range of sea. 



