GALLERY.] 
NATURAL HISTORY. ( Fossils. ) 
87 
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 7. 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- 
tice, from Balderton in the county of Nottingham, presented by Dr. 
Bland the splendid specimens of 7. intermedius, I. lonchiodon , 7. 
communis, all from Lyme Regis ; the 7. longipinnis and 7. longiros - 
tris from Whitby, &c. 
In the Wall Case 6 will be found the remains of various mammalia 
belonging to the order Ruminantia. 
In the Wall Case 7 are arranged the fossil carnivorous mammalia, in- 
cluding skulls and various other portions of the skeletons of bears, chiefly 
from Gailenreuth in Franconia ; remains of the hyaena from the caverns 
of Torquay and Kirkdale. Certain insectivorous mammalia are also 
placed in this case, as well as the very valuable specimen presented by 
W. J. Broderip, Esq., the lower jaw of the Phascolotherum Buck- 
landi, from the Great Oolite of Stonesfield, Oxfordshire. 
Room V. 
This room contains the collection of Fossil Fishes, arranged after M. 
Agassiz’s system, as developed in his w 7 ork, Recherches sur les Poissons 
fossiles. They are divided into four Orders, namely, the Placoids, the 
Ganoids, the Ctenoids, and the Cycloids. The first of these orders com- 
prehends individuals mostly of considerable dimensions, whose skele- 
tons, by reason of their soft, cartilaginous nature, are less enduring; 
their fossil remains therefore generally occur as small detached portions 
only of the whole body, such as teeth, palates, and dorsal fins, some of 
which, as smaller objects, are under arrangement in the Table Cases 
(1 to 4). The remaining three orders of this class, demanding ample 
space, are placed in, and on the top of, the upright wall cases on the south 
side of the room. The red figures on the labels of the genera refer to the 
larger suspended boards bearing the names of the orders and families ; 
while the names of the species are written on labels variously tinted, in 
accordance with the coloured tablets within the cases, indicating the geo- 
logical formations to which the specimens respectively belong. 
The Order of Ganoids or Goniolepidoti, (names derived, the one 
from the lustre, the other from the angular form of the scales of these 
fishes,) occupies the Cases* 1 to 16; it is divided into twelve fami- 
lies, namely, the Cephalaspidians, Acanthodians, Dipterians, Lepidoids, 
Sauroids, the Celacanths, Pycnodons, Scleroderms, Gymnodons, and 
the Siluroids ; with two other of Cuvier’s families, of which specimens 
are wanting in the collection. 
* By “ Case 1, 2, 3, &c.,” the divisions or compartments of the principal Wall 
Cases are understood. 
