Margarita elegantissima, Bean.
Cemoria Noachina, Linn.
Calyptraea chinensis, Linn.
Dentalium abyssorum, Sars.
- -, var. tarentinum.
- dentalis? Linn.
Rhynchonella psittacea, Chemn.
Anomia ephippium, Linn.
- striata, Brocc.
Ostrea edulis, Linn.
Pecten opercularis, Linn.
- islandicus, Mull.
- pusio, Pennant.
Mytilus edulis, Linn.
Modiola modiolus, Linn.
Pinna pectinata, Linn.
Pectunculus glycimeris, Linn.
Arcta lactea, Linn.
Nucula Cobboldiae, J. Sow.
- tenuis, Mont.
Leda limatula, Say
- pernula, Mull.
- myalis, Couthouy.
M. plicata, Sars.
Puncturella Nouchina of Forb. & Hanl., and of Jeffreys.
One young specimen from the Middle Glacial.
D. costatum, J. Sow. Two specimens from the Middle Glacial. The costae are as broad as, but less prominent than, in the Crag shell; but this may be due to wear. It is possible that the specimens may be only the upper portions of D. abyssorum.
A. squoemula of Woodward's list. Common in Middle Glacial.
Sitka and Norway.
Lower beds of Red Crag only. Middle Glacial of Stevenage, Herts, only.
Very common in Middle Glacial, but fragmentary.
A specimen in Brit. Mus. said to be from Bridlington.
Worldwide.
M. vulgaris of Woodward's list.
Fragments in Cromer Till.
Very common, but small, in Middle Glacial; dies out in the upper beds of the Crag.
The hinge of the Middle-Glacial (perfect but small) specimen is too worn for certain identification.
The Lower- and Middle-Glacial and Bridlington specimens show a tendency to depart from the Crag form in having the peculiar ornamentation more confined to the upper and central part of the shell. Represented by N. Lyalli on the N.W. coast of America.
Yoldia oblongoides of Woodward's.
British also [list.
Three specimens in Brit. Mus., two from Postwick, a Crag locality, and one from Runton, which (except the forest freshwater bed) is Lower Glacial only.
