Praeger— Fossils at Alexandra Dock, Belfast 41 



Ostrea edulls, var. hippopus, Lamb. 



In the upper clay, frequent, and of immense size. One specimen weighed 



over a pound and three quarters. 

 Pccten varius, Linn. 



Single valves not uncommon, perfect specimens rare. 

 Pecten opercularis, Linn. 



Fine examples are scattered plentifully through the upper clay ; in the yellow 



sand single valves are abundant. 

 Pecten maximus, Linn. 



In the upper clay, here and there, regular layers of the large shells of this 



species and of the Ostrea were observed. 



* Pecten pusio, Linn. 



One valve of this def ormed-looking species was found in the lower clay. A 

 rare shell in our present waters, and not hitherto observed in the Estuarine 

 Clays. 

 Mytilus edulls, Linn. 



The Mussel is plentiful in the top clays and yellow sand, reaching in the 

 latter its full limit of size. In the upper clay it is unknown, but appears 

 again in the lower clay in a crumbling condition. 



* Mytilus edulls, var. pellucldus, Penn. 



Examples of this perhaps not distinct variety are frequent. 

 Mytilus modiolus, Linn. 



Not at all common. I obtained one perfect specimen and a few fragments 



in the upper clay. 

 Mytilus Adriaticus, LamJc. 



Rare ; a few young shells in the upper clay. 

 Nucula nucleus, Linn. 



Diffused through the upper clay. 



* Area tetragona, Poli. 



One complete specimen in the bed of yellow sand. 

 Montacuta bidentata, Mont. 



This tiny bivalve is scattered plentifully through the upper clay and yellow 



sand. 

 Montacuta ferruglnosa, Mont. 



In the upper clay, very rare. 

 Xiucina borealls, Linn. 



In the uppermost deposit at the Dock large specimens of this shell occurred, 



but only as single valves. 

 Axlnus nexuosus, Mont. 



Generally diffused, and abundant. 



