170 Stewart — Mollusca of the Boulder Clay. 



the Quarterly Journal of the Geological Society of London. Mr. Reade appre- 

 hended the importance of this bed, and in his communication gives a section 

 and interesting notes. The deposit at this place is well exposed, and differs 

 much from those of the foregoing localities. It consists of gravel, with sub- 

 ordinate layers of sand and clay, the combined thickness of this series being 

 about twenty feet. The gravels are overlaid by abed of ordinary Boulder Cla y, 

 about ten feet thick. The base is not seen. The gravels can be traced along 

 the road for some fifty or sixty yards, and yield a number of very interesting 

 shells, univalves preponderating. 



LIST OF THE MOLLUSCA OF THE NORTH-EAST OF 

 IRELAND. 



I gratefully acknowledge that in compiling this list I received valuable 

 assistance from Dr. J. Gwynn Jeffreys. F.R.S., who, with his usual kindness, 

 undertook the identification of such of my shells as were in any degree doubtful. 



Rhynchonella psittacea. Chemnitz. 



Ballyrudder, County Antrim, Jeffreys and Hyndman. Report Brit. 

 Assoc, 1859. 



Anomia ephippium, Linn. 



Belfast Waterworks. Bryce. Phil. Mag., Vol. XXVI., p. 433: 

 Ballyrudder. Jeffreys and Hyndman. 



Ostrea edule, Linn. 



Belfast Waterworks. Bryce. 



Pecten maximus, Linn. 



Belfast Waterworks. Bryce. 



mytilus edulis, Linn. 



Woodbum, Bangor, Ballyrudder, S. A. S. ; Belfast Waterworks, Bryce ; 

 Ballyrudder, Jeffreys and Hyndman. In great abundance in a bed of stiff 

 blue Boulder Clay on the banks of the Crumlin River. 



