GALLERY. ] NATURAL HISTORY. (Fossils.) 85 
the lower jaw and other parts of the cranium, vertebrae, &e., of the 
huge reptile ( Mososaurus Sancti Petri ) from the St. Peters Mountain 
near Maestricht, presented, in 1784, by the celebrated Peter Camper, 
and figured by Cuvier a portion of a new species, from Lyme Regis, 
of the remarkable genus of flying reptiles, the Pterodactylus of Cuvier, 
described and figured by Buckland in the Transactions of the Geological 
Society, under the name of P. macronyx : together with a coloured 
cast of Pterod. longirostris of Cuvier from Solenhofen, the quarry 
of which place has also furnished the small lamina of lias on which may 
be observed the impression (with some of the osseous substance re- 
maining) of the last two articulations of the toe of a flying animal, con- 
sidered by Spix as related to the Vampire, but which is more probably 
a large and distinct species of Pterodactyle. 
The whole of Case 3 is occupied by the osseous remains of Iguano- 
don, chiefly from the strata of Tilgate Forest in Sussex ; a suite, 
which, together with the great group of bones from Maidstone embedded 
in Kentish rag, (in a separate glass Case placed at present under the 
central window,) has furnished Dr. Mantell with highly valuable 
materials for the illustration of that extraordinary reptile, scarcely less 
remarkable in its osteology than the gigantic animal (Wall Case 2) of the 
same order, discovered by that naturalist, and to which he has given the 
name of the Wealden Lizard ( Hylceosaurus ), to express the circum- 
stance of its occurring in the strata of that geological formation. 
In the Wall Cases 4 to 6, of this Room, and in all those of Room 
IV., are arranged the order Enaltosauria, or feea Lizards, of the sub- 
division of which the genera Plesiosaurus and Ichthyosaurus are tne 
principal types. Among the species of the former may be particularized 
the Plesiosaurus Hawkinsii , chiefly from the lias quarries of Street, and 
thus named by Mr. Owen in honour of the author of the work in which 
most of the specimens are figured and described that formed his col- 
lection, now partly deposited in this Gallery ; — the species from Lyme 
Regis, first described by Mr. Conybeare, and named P. dolichodeirus , 
its neck being nearly equal in length to the body and tail united ; the 
P. rugosus from the lias near Belvoir Castle, presented by H. G. the 
Duke of Rutland, being a unique nearly complete specimen of this 
species; — the specimen of a Plesiosaure, of which an account and figure 
have been given in the Philosophical Transactions for 1719, by Mr. 
Stukeley, who mistook it for a crocodile. 
Room IV. 
In and on the Wall Cases of Room IV. are placed the larger speci- 
mens of the various species of Ichthyosaurus, or the fish-lizard, so de- 
nominated on account of their having in a recent state clearly presented 
the external appearance of certain orders of fishes combined with the 
internal organization belonging to the Saurian reptiles. The most 
striking specimens are the I. Platyodon in the central Case, and various 
bones of its gigantic variety on the top of the same Case and in Case 2, 
such as the head cut transversely to show the internal structure of the 
jaws ; the carpal bones of one of the extremities, &c. : all from the 
lias of Lyme Regis ; — a new small species I. latifrons, in which the 
spiracle on the top of the head, between the eyes, claims particular no- 
