40 
NORTH GALLERY. 
[UPPER 
and 8), Room VI. Not any of these can be certainly identified with 
living Shells; and the species which they most resemble are now 
found at the Cape of Good Hope, the western coast of South America, 
and other localities remote from those where the fossils have been* 
found. 
SHELLS OF THE SECONDARY STRATA. (Rooms V. & VI.) 
5. Chalk, Gault, and Green-sand (Cretaceous System). (Table 
Cases 1 and 2, Room V.) The characteristic Shells of the Chalk are 
Inocerami, related to the recent Pearl-oyster ; Spondyli ; Scallops (Pec- 
ten), of peculiar form ; " Cockscomb " oysters, and species of Lima 
and Pleurotomaria. One peculiarity of the Chalk Fossils is, the con- 
stant absence of the interior pearly layers of the shells, which have 
been removed subsequent to their imbedding. In the Green-sand 
strata, Trigonice abound, and peculiar bivalves, of an extinct family (Hip- 
puritidce), related to the recent Chama. Case 1, Room VI. 
6. Jurassic, or Oolitic Shells. (Cases 2 and 3, Room V.) The 
shells of the Portland stone, Bath stone, and other Oolitic rocks, and of 
the Lias, include numerous species of Trigonice, the internal casts of 
which are often found, whilst the shells have been dissolved and removed 
from the rock; they are called " horse-heads" by the quarry-men, and 
are sometimes silicifled, and contain traces of the shell-fish itself. 
Amongst the Oolitic oysters, are some whose shells have been moulded 
on TrigonicR and Ammonites. 
7. The Shells of the Triasstc System in Case 4, Room V., con- 
sist of the original specimens figured and described by. Dr. Klipstein, in 
his work on the fossils of the salt-marls and Alpine limestone of 
Austria. 
PALAEOZOIC SHELLS. 
8. Magnesian Limestone (Permian), of Northumberland and 
Durham. (Case 4.) 
9. Carboniferous Ltmestone, and Coal-measures of Britain and 
Belgium. (Cases 4 and 5.) Chiefly from the collection of Professor 
De Koninck, of Liege. 
10. Devonian System. (Case 5.) Devonshire and the Eifel. 
11. Silurian System. (Cases 5 and 6.) Presented by Sir Roderick 
Murchison. Bart. K.C.B. 
J chambered shells (Cephalopoda). 
The Shells of the chambered univalves (Cephalopoda), related to the 
recent Nautilus and Cuttle-fish (Sepia), are placed in the Table Cases 
(7 to 12 and 14) of Room V. 
In Case 10 are placed the curious fossils named Apiychi and Tri- 
gonellites, now known to be the operculum or covering to the mouth of 
the shell of the Ammonite. 
Jn Case I 1 the fossil Nautili are displayed. Those from the London 
Clay of llighgate and Sheppey are specially worthy of notice. 
