416 REP ORT—185S0. 
southern forms in the same waters is amply proved by the taking in the 
same haul, in 348 fathoms off the south of Ireland, such extreme forms 
as Fusus islandicus and Cassidaria tyrrhena, both fine and living. Their 
occurrence therefore together in an old deposit does not imply that either 
the northern or southern species must have been transported thither. 
The Hstuarine Deposits 
of the north-east of Ireland occupy a considerable area, inland, of the 
margins of the loughs and estuaries indenting the coast. Few deposits 
are so rich in species, or so well preserved. Neither in Scotland nor Eng- 
land is there any one that can be compared with them in this respect. 
The building of the various docks at Belfast has enabled Canon 
Grainger, Mr. 8. A. Steward, and Mr. R. Lloyd Preger to collect 
largely, and, in doing so, to examine the nature and stratification of the 
various members of the group. In hardly two sections are the features 
alike. In Spencer basin Mr. Stewart found a thickness of 20 feet of 
clay, the upper portion being crowded with littoral shells, the middle 
with Thracia and species pertaining to a fauna living in from five to ten 
fathoms, and at the base, or lower portion, a zone of scrobicularia. Mr. 
Preger! in the Alexandra Dock found sand, blue clay, peat, sand, 
re-assorted boulder clay, and boulder clay with striated rocks. At 
Magheramorne, on the left bank of Larne Lough, the clay is above the 
surface, and may have been brought up by the pressure and thrust of 
the adjacent railway embankment. Here the zones of life are less marked, 
and the several species are more grouped than seems the case elsewhere. 
The fauna in different localities varies much—thus at Belfast, Thracia con- 
vexa, Cardium echinatum, Lucinopsis undata abound. At Magheramorne 
these are rare, or absent, and Modiola modiolus, Lima hians, and Tapes 
virginea are in quantity, and these are very scarce at Belfast. Polyzoans 
are rare; I know only one obtained on a pecten, at Magheramorne, by 
myself. The microzoa have been taken in hand by Mr. Joseph Wright, 
F.G.S., Belfast, who is still at work upon them. In thickness the clays 
are very inconstant, depending apparently more upon the breadth of the 
estuary than upon their proximity to the water line. Thus in the Spencer 
basin they have, been found 20 feet thick, and at the Curran Larne only 
3 feet, the one estuary being much narrower than the other. 
Considering the richness of the fauna, it is singular that some of the 
molluscs reached an enormous size, and the paucity of the gastropodous 
mollusca is striking. Of the hundreds of bivalves that have passed through 
my hands I do not remember one that had been perforated. It may be from 
this cause that the bivalves grew so large. From Magheramorne I have 
taken oysters 5 inches across, Tapes virgineus 3 inches, and others in 
proportion. The Pholades (P. crispata) are the largest known, run- 
ning up to 5 inches by 25. These are found only in the Belfast exca- 
vations. Assiduously as the beds have been searched, femains other 
than molluscs and microzoa are rare, most of them being single speci- 
mens, except Echinus miliaris, which is not uncommon at Belfast. 
The shells in the lists of the mollusca of the estuarine clays of the 
north-east of Ireland have been obtained chiefly from the estuaries of 
Belfast and Larne, at Magheramorne. Strangford Lough, Limavady, and 
1 Proc, Belfast Nat. Field Club, 1888, 
