30 Praeger — The Estuarine Clays 
through the strata in the Lagan Estuary, hut in the Quaternary Estaarine 
deposits in other parts of Ireland, and in England and Scotland. At the 
Alexandra Dock we hare first several feet of clay and sand, which bed was still 
in course of formation when the works were commenced, its upper surface being 
a little above low water mark. Below this is a bed of yellow sand, containing 
many shells, which probably corresponds in age with the flint-bearing gravels 
the Kinnegar at Holy wood and the Curran at Larne. Immetotely underlying 
this is that very distinct deposit, the Estuarine Clay, which at Belfast, Lame, 
and other points around our coasts, possesses the same peculiar features and 
yields the same characteristic fossils. Below this is a bed of peat, corresponding 
with the submerged peat which occurs in so many places on the shores of t 
British Isles. This rests on fine red glacial sand, the same deposit which occurs 
at Malone and at the Knock ; which rests in turn on very fine tough red clay- 
re-assorted Boulder Clay. Underlying this is the Boulder Clay proper, with 
glacially striated pebbles, which, Anally, overlies the New Bed Sandstone. These 
last two formations were not exposed at the Dock, but there is no doubt they 
underlie the red clay, as they do at other points in the immediate vicinity. We 
have thus an unbroken series of deposits, stretching from the Boulder Clay 
Period to the present day, and “ offering,” says Mr. Stewart, “ perhaps the bes 
means of filling up the gap in geological history between the close of the Glacia 
Epoch and the present day.” . , , . 
So much for the general section. I now come to a more minute description 
of the deposits, and shall begin with the section which is shown in Figure 1. 
This is as follows A M 
1 Blackish clay, with sandy layers, of a depth of six to seven feet, the surface 
between tide marks. Characteristic shells of this deposit are -.-Mya arenana 
Gardium edule, Tellim Batthica, Mytilm edulis. Mya occurs m beds of 
thousands, the sheUs all in the position in which they lived, and generally with 
the siphonal tube preserved. Cardium is also very abundant. This bed yielded 
two specimens of Helix nemeralis, no doubt washed into it by surface water; 
and unusually large single valves of Zucma borealis were not unfrequent. 
2 Two feet of coarse yellow sand, with abundance of shells, and also tiun 
layers' of twigs and hazel nuts. The shells are often much worn, and generally 
occur as single valves, and the deposit has all the appearance of an old sandy 
beach Pecten opercularis, Zittorina litorea, Mytilm Mis, occurred here 
abundantly, and fine specimens of Tapes pullastra, Tdeemsatus mi Thracia 
convexa, which two latter species are not now found living m Belfast Lough- 
Among the rarer forms which were noticed were :-F,ssurella Grceea Troehm 
magus. Patella vulgata, Turns amtiqum, Murex erinaeeus, Cypma Ewopcea 
Anemia patellifmmis, Venus lincta, Cypnrn Islandica. Six species new 
Estuarine Clays were observed :-Fusm gracilis, Anemia striata, Tapes 
Venus faseiata, V. exoleta, Area tetragona. Several worn valves of 
piperata were noticed-this shell will be referred to later on-they had probab y 
been washed from the underlying beds. 
