MOLLUSCA (EXCEPT CEPHALOPODA). 
127 
branchs the Iludistae are remarkable and characteristic. 
The early Tertiary fossils are evidence of a gradual change 
to present conditions, botli in the character of the inolluscan 
fauna and its eventual distribution in the same provinces as 
are at present recognised. 
V. CEPHALOPODA (Head-foot), of which the Nautilus 
and cuttle-fish are examples. These are exhibited in 
Gallery VII. We shall therefore leave them for the present, 
and confine our attention to Gallery VIII., which contains 
fossil shells of only the first four Classes, viz. : — 
AMPHINEURA, GASTROPODA, SCAPHOPODA, 
LAMELLIBRANCHIA. 
Tt will be most convenient to start with the British 
specimens. Beginning at the main entrance to the Gallery, 
and following the numerical order of the Table-cases, these 
are arranged under the larger stratigraphical divisions, with 
the newest first. 
Post-Pliocene. The marine forms are separated from 
the non- marine, and are arranged under geographical districts 
in the following order : S. England, Selsea, &c. ; S.E. England, 
including Norfolk; N.E. England, chiefly Yorkshire; W. 
England, Gloppa, near Oswestry ; Wales, Moel Tryfaen ; 
Ireland, the Wexford gravels and Belfast ; Scotland, Clyde 
series ; E. Scotland, chiefly Hyer’s Burn and Golspie; W. 
Scotland, including the Lewis. Some of these date from the 
Glacial period, others are later, as indicated on the label in 
each instance. They come from raised beaches, glacial drift, 
and other deposits, and are often found far above present 
sea-level, as much as 1350 feet at jMoel Tryfaen, 1120 feet 
at Gloppa, and 1200 feet at Calbeck Castle, near Dublin. 
Some writers have supposed that they were carried to these 
heights by moving ice. Most of the shells belong to species 
still existing, and they are as a rule characteristic of northern 
seas, but southern forms are sometimes associated with them. 
In the following list of the more important species, the 
letters N, S, and E respectively denote the Northern, 
Southern, and Extinct forms : — Gastropoda : Bittium reticu- 
lattim (S), Borcotrcrphoii YTrophoii] clathratum (N), Littorina 
littorca (N), Ncjotitnca antiqua (N), Tricolia \^I^kasianella\ 
pulla (S), Tritonofusus Lcclcenhiji (E), Turritdla communis 
(N). Lamellibranchia : Acila \^Nucula\ Col)holdiae QL), Area 
lactea (S), Callista [ Vcnus\ cliionc (S), Cerastodervia \Cardium\ 
Gallery 
VIII. 
Gallery 
VIII. 
Wall-cases 
19 . 
Table-cases 
1-16. 
Centre- 
cases Al- 
A3 and A7. 
Table-cases 
1 & 2 . 
