iG. 192a. — Photograph of the natural size of a tooth of the gi*eat shark, 

 Carcharodon megalodon, from the bone-bed of the Red Crag of Felix- 

 stowe, Suffolk. The specimen is in the author's cabinet. It is three 

 times the length of the largest living shark's tooth, and the fish which 

 bore it was probably 100 feet in length. A kind of sandstone is seen 

 adhering to a part of the surface of the tooth, which shows that this tooth 

 (like many others found in the Red Crag) had been embedded in an 

 earlier sandy deposit (the Diestien sands) before it was washed into 

 the Red Crag. 



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