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plate may be supposed to agree, has not been united, but that it has 
been connected by interposed membrane. This part happens, fortu- 
nately, to be in so good a state of preservation, as to allow the several 
osseous parts of this plate to be distinctly made out. At a, is seen a 
part of the anterior appendix ; at h, is the anterior branch ; at c, the 
posterior branch ; and at d, is the posterior appendix. 
In Verona, and chiefly in the Valley of Ronca, fragments of tortoise- 
shell are found ; and, from the rugous state of the outer surface ol 
some of these, I have little doubt of their having belonged to some ot 
these animals, whose coverings were partly coriaceous ; for in these, 
although the outer surface of their covering would be smooth whilst 
living, they would be thus rugous after the death of the animal. 
Mr. Johnson, of Bristol, was lately so fortunate as to find, at the 
Old Passage, in Gloucestershire, some fossils of a very curious appear- 
ance and form. One of these is respresented Plate XVIII. Fig. 1. 
This, with several others, most of which are much larger, and possess 
a fine polish, and are of a deep black, I conceive to be the digitated 
terminations of the sternal plate belonging to one ot these animals, 
with a partly membraneous or coriaceous covering. These fossils 
approach the nearest to the corresponding parts in the Trionyx cari- 
natus of M. Geoffroy St. Hilaire. One of the fossils found by Mr. 
Johnson is decidedly the osseous plate belonging to the posterior 
appendix, and resembles very much, in its form and rugous surface, 
the corresponding part in Trionyx JEgyptiacus, of M. Geoffroy St. 
Hilaire, but is full six times as large. 
I must not conceal from you, that the ingenious gentleman who 
possesses these fossils is disposed to entertain a different opinion, and 
to believe that they are the parts of the jaw or palate of some fish. 
This must remain to be determined by some moie lllustiative and ana- 
logous specimen : until then, I shall hold my opinion with diffidence ; 
for, as I have had already occasion to notice, eiioi in these incjuiiies 
is very easily fallen into. Thus has Faujas St. Fond, in the elegant 
vol. hi. 0 0 
