MOLLUSCA (except CEPHALOPODA). 
131 
Clay fossils are the long tubes formed by the boring 
lainellibrauchs Teredo and Teredma, allies of the modern 
“ ship-worm.” Pyrula Smithi and Xeiwphora externa are 
noticeable gastropods, jlporrhais Sowevhji is a gastropod 
from Oldhaven Gap. Characteristic of the Woolwich beds 
are Corhieida [Gyrena^ dulwiehensis, Corhula rcgidhiensis, Pith- 
arella Pickmani, a freshwater shell, and Ostrea bellovacina, 
of which a fine mass is exhibited. From the Thanet Sands 
come Cyprina Morrisi, Pholadomya eimeata, and Mcretrix 
orbicularis. In the middle of the Gallery stands a slab of 
“ Bognor Eock ” from the London Clay of Bognor, largely 
composed of shells or the casts of shells of Cardita Brony- 
niarti, Glycimcris brevirostris, Volsclla \^Modiokd\ 
eleyans, Voluta denudata, Pyrida Smithi, Natiea hantoniensk, 
and the annelid Vennebis boyuoriensis. Other masses of the 
same age from Fareham, Hants, are placed on the wall; one 
is full of shells of the lamellibranch Pinna ajfinis, the other 
(Elate V.) contains in addition Glyeimeris birvirostris and 
the smaller G. deeussata. 
Cretaceous. This series is rich in specimens described 
by G. A. jMantell, Samuel Woodward, James Sowerby, 
J. de C. Sowerby in Dixon’s “ Geology of Sussex,” H. Woods, 
and others. Except those from the estuarine or lacustrine 
deposits of the Wealden series, all are marine. First come 
the shells from the Upper and Middle Chalk and Chalk 
Eock, in other words from those zones that are of Senonian 
and Turonian age. Among these the lamellibranchs of the 
genus Tnoccramus are conspicuous and their disintegrated 
shells enter largely into the composition of the Chalk : 
I. Cuvieri may attain a width of 18 inches, some large pieces 
of its hinge are shown ; I. labiatns gives its name to a 
Turonian zone; the original specimen of the widely dis- 
tributed I. Crippsi is of historical importance. Spomlylus 
spinosus with the long spines well preserved (Fig. 70), and 
the five-ribbed fan-shell Neithca quinriuccostata (Fig. 71 a'), 
are characteristic of the Upper Chalk; the gastropod Plm- 
rotomaria p>erspeetiva is Turonian. Here too are tubes of 
Teredo ampliisbseua, and several specimens of the curious 
liadiolites Mortoui, one of the Eudista?. (see p. 143). 
Following on these are shells of Cenomanian age, 
coming from the Lower Chalk, Upper Greensand, and Chalk 
Marl. Here may be noted the cocks-comb oys,\jQv Alcetryonia 
earinata, the scollops Cldaniys Beaveri and C. asper, of which 
the latter gives a name to the “ Pecten asper zone,” tire 
K 2 
Gallery 
VIII. 
Centre 
and 
Table-case 
5. 
Between 
Wall-eases 
3 & 4 
and 
4& 5. 
Table-cases 
6-9. 
Table-case 
0 . 
Wall-ease 
5a. 
Table-case 
6 . 
Table-cases 
6 & 7. 
