Mantellian Museum at Lewes. Tt} 
extraordinaire que tous ceux dont nous avons connoissance). 
It is indeed extraordinary not only from being the largest 
amphibious or terrestrial animal hitherto know n, but frou its 
peculiar structure as an herbivorous masticating reptile. These 
preliminary observations are chiefly made, to prove to your 
country readers, how much may be done for the promotion of 
science, even in situations not favourable to its pursuit, at a 
distance from public museums, and removed from the excite- 
ment produced by associating with others engaged in kindred 
studies. 
I now proceed to describe the museum. ‘The room in 
which the objects are placed has been recently erected b 
Mr. Mantell for the purpose, and is well lighted from above ; 
the larger specimens are arranged in glass cases, and the 
smaller ones in drawers below. It has already been stated 
that the collection of chalk fossils is the finest in the kingdom ; 
it will not be necessary to particularise them, except those 
which are extremely rare, but it may be observed, that the 
matrix in which the most delicate anima! remains are eaibedael 
has been partly removed with a degree of science and care 
that I have noticed in no other museum, and they are dis- 
played to the greatest advantage. The be autiful series of 
fishes allied to the zeus or doré ée, from the chalk pits near 
Lewes, are particularly interesting: one of them is a matchless 
specimen, the mouth being open and entire, and the tongue 
exposed ; but the most remarkable circumstance is the un- 
compressed and perfect form of the bedies, which was doubt- 
less chiefly owing to the preservation of the air bladder, for it 
appears unbroken in many of these specimens. THis Is an 
important fact, as it proves that the bodies were completely 
incased in the chalk, before the putrefactive process had com- 
menced, and adds probability to an opinion I advanced in a 
former edition of my Introduction to Geology; that the form- 
ation of many beds in the secondary strata was effected by sub- 
marine eruptions of hot water, saturated with ear thy matter, 
which destroyed the animals previously existing, and formed 
around them a siliceous or calcaréous incrustation, that pro- 
tected their remains from destruction. * 
In some of the fossil fishes, the dorsal fins, gills, and teeth 
are preserved, as well as the air bladder and tongue; the 
scales are also very distinct. There are many fine specimens 
of Ventriculites, first described by Mr. Mantell in the 11th 
* M. Alex. Brongniart to whom I sent a copy of that work has recently 
adopted a similar theory to what I had advanced in 1815, that some of the 
siliceous strata in the Paris basin were deposited by thermal waters holding 
siliceous earth in solution. 
