16 Dr Knox on the size of the Teeth in Sharks. 



but, at the same time, you will see that I could not avoid it, 

 without a great sacrifice of proper feeling on such a subject. 

 As you have, on all occasions, shown a laudable desire cor- 

 rectly to adjust such questions, you will, I trust, excuse me 

 for troubling you with so much on this subject, and for re- 

 questing that you will occupy a portion of your valuable 

 Journal, by giving the earliest insertion to these remarks, in 

 order that the effects of inaccuracies of statement may be as 

 speedily as possible counteracted. I am, 



Dear Sir, yours very sincerely, 



Royal Military Academy, S. H. Cheistie. 



Ijth February 1826. 



Aet. IV. — Observations on the size of the Teeth in Sharks, 

 compared with the Fossil Teeth of an animal analogous to 

 the present Shark, and described by Messrs Lacepede and 

 Faujas St Fond, in the " Annates de Museum.'''' By Ro- 

 bert Knox, M. D. F. R. S. £., &c. Communicated by the 

 Author. 



-The fossil tooth of a Shark discovered at Dax, by Mr de 

 Borda, was examined by the Count Lacepede, and found to 

 measure three inches and three lines in length from the base, 

 and three inches in breadth. A comparison of this tooth, with 

 others belonging to the common Squaluss Carchariu of Linne, 

 led this distinguished naturalist to conclude, * that, in the 

 former world, previous to the aera of a. deluge, there must 

 have existed sharks seventy-nine feet in length. Faujas St 

 Fond adopted these measurements of Lacepede in the deter- 

 mination of the probable length of a shark, a tooth of which, 

 in a fossil state, was brought to him from the quarries of 

 Montrouge, in the environs of Paris, and he concluded, 

 (Annal. de Mus. t. ii. p. 107,) that the animal to which the 

 tooth belonged must have been about fifty feet in length, at 

 the least. 



The memoir of Mr F. St Fond is accompanied with a 



• Tom. i. p. 205. 



