The American Museum Journal 



Vol. IX DECEMBER, 1909 No. 8 



THE GIANT OF ANCIENT SHARKS. 



AT the entrance of the Hall of Fossil Fishes there is now exhibited 

 a restoration of the jaws of a shark (Carcharodon megalodon) 

 which lived along the coast of South Carolina, in Tertiary time. 

 There can be no doubt that this was the largest and most formidable fish 

 li\nng or extinct of which we have any record. The jaws of a fully 

 grown specimen measured about nine feet across and must have had a 

 gape of five or six feet. The teeth themselves average about six inches 

 in height in the middle of the jaw, and they gradually decrease in size 

 in the direction of the sides of the mouth, the smallest teeth measur- 

 ing about two inches. 



In the present restoration the teeth have been arranged as in the li^•- 

 ing species of Carcharodon, the great White Shark or ]Man-F,ater, for 

 there can be no question that the fossil shark differed in no essential 

 structure from its modern relative. Accordingly the jaws of Carcharo- 

 don rondeleii were carefully measured (a splendid pair having Ijcen 

 loaned by the ^Museum of Natural History of Paris, through the cour- 

 tesy of Professor Valliant), and the model was prepared according to 

 scale, that is, in accordance with the proportions of the teeth in the ex- 

 tinct and in the living form. The fossil teeth were then arranged on 

 the jaws in the same number of row^s and in the same number of banks 

 of graded sizes. Fortunately for this purpose a large assortment of teeth 

 of the fossil shark was available, out of which an almost complete denti- 

 tion was selected. This material had been collected during many years 

 by a resident of Charleston, Joseph Cohen, and the collection was se- 

 cured through a grant from the Cleveland H. Dodge fund. 



The accompanying picture gives an idea of the impressive size of 

 the ancient Carcharodon. Indeed from the teeth alone one can form a 

 reasonably accurate estimate of the dimensions of the fossil fish, for it is 

 known that a specimen of the living species in which the largest tooth 

 was one and one half inches in height measured twenty feet, and that 

 another having teeth three inches in height had a total length of forty 

 feet. It therefore follows that the length of the Carolina shark whose 



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