Petrifactions found in St. Peter’s Mountain . 451 
bone from the fame mountain in his valuable collection, but 
fent to him under another name, I am convinced it belonged 
formerly to a turtle ; firft, becaufe I have from the fame 
mountain the intire back of a turtle, four feet long and fix- 
teen inches broad, a little damaged at the fides, and a pretty 
large fragment of another turtle, in my pofleffion. sdly, Be- 
caufe 1 have a fimilar one, but fo placed within the matrix as 
to (hew the infide, which is perfectly analogous to the infide 
of that piece in the back of a large turtle I got in London, by 
the favour of Mr. Sheldon. 3dly, Becaufe I have amongft thefe 
bones the lower jaw-bone of a very large turtle, of which 
the crura, though not intire, are leven inches long, and 
diftant from one another fix inches ; the thicknefs is equal ta 
2 1 in c h . 
All thefe fragments prove the frequency of turtle bones 
amongfi: the other fulfil bones found in the mountain neat" 
Maeftricht. 
Dr, Michaelis wrote to mefome time ago, that the above- 
mentioned fragment, in Mr. J. Hunter’s Collection, be- 
longed to a bird ; which I could hardly believe, as I never had 
feen in any collection whatfoever, either in London, Paris, 
Bruffels, Gottingen, Caffel, Brunfwic, Hanover, or Berlin, 
nor in my own country, any foflil bone belonging to a bird. 
1 know there is a fmall one defcribed in the Abbe Rozier’s 
Journal de Phyfique, for March 1782, which is at prefent in 
the collection of M. d’Arcet, at Paris. I expeCt alfo from 
Montmartre a fmall leg of a petrified bird ; but thefe are the 
only ones I have ever heard of, thofe of Stonefield, near Wood- 
flock, being mo it undoubtedly of fifhes. I think it is a cir- 
eumftance worthy the attention of the curious, that no human 
Vo.L. LXXVI. Nnn bones, 
