28 Stewart— List gf Estuarine Clay Fossils. 



examining them, though I have in my possession some of the shells from 

 the Estuarine Clay of the Bann. In such inlets as those of Loughs Larne 

 and Strangford, into which there are no rivers of any note carrying sedi- 

 ment, these Post-Pliocene clays are indicated by accumulations of small 

 extent, but characterised by the presence of shells, in most part the same 

 as those living in the adjoining waters. 



A list of the Belfast clay shells was made out by John Grainger, 

 Esq., and published by the British Association in their Report for 1852. 

 A second list by Mr. Grainger, recording all the species known to occur 

 in this bed at that date, was published in the Natural History Review for 

 1859. By the excavations for the recently constructed floating dock and 

 basin, I have been enabled to examine this clay to a depth of twenty feet, 

 over a considerable area. The results are the addition of a goodly number 

 of species to Mr. Grainger's lists, and the conviction that there is evidence 

 that since the basement portion of that clay was laid down, there have 

 been several oscillations of the sea-level ; these oscillations can be shown 

 by a comparison of the different sets of shells, found at various depths in 

 the clay. 



The Larne Lough Estuarine Clay may be seen on the shore close to 

 Magheramorne railway station : shells occur in it abundantly, many of 

 the testacea being among our rarer species. This deposit is rich in Fora- 

 minifera, and in the smaller forms of JMollusca, especially univalves. It 

 has been only slightly examined, and would doubtless yield many more 

 fossils if scrutinised as closely as the corresponding bed at Belfast. At 

 Strangford Lough I have seen the Estuarine clay near Newtownards, but 

 have had little opportunity of investigating the bed at that place. 



