H. T. MENNELL ON THE MOLLUSCA. 257 
with the Greenland and glacial shells we might exclude from our 
list the smaller and critical genera of Odostomia, Rissoa, Huli- 
mella, which have probably not been observed in either, and for 
comparison with the glacial we should of course omit the Nudi- 
branchs and Tunicata, of which no remains can be found in the 
fossil beds. Then the larger percentage of subarctic and glacial 
species will be very evident. Of the species obtained 7 (+) were 
living at the period preceding the glacial, but disappeared during 
that age, hence they may be considered as more southern types, 
and their small number is striking. 
Of the species recorded in the list, Eulima nitida, E. gracilis, 
and Rissoa cimicioides, are new to our local fauna; Syndosmya 
intermedia, not included in Mr. Alder’s catalogue, has only been 
met with once previously by Mr. Howse. Margarita cinerea is, 
if fossil, (and there can, we think, be no doubt of it,) new to the 
English Pleistocene Fauna, having only hitherto been recorded 
from the Clyde and from the Antrim Turbotbank. 
Several species recorded by Mr. Alder in his Catalogue of the 
Mollusca, published in our Transactions, as of great rarity, were 
met with in considerable abundance, ¢.g., Trophon Barvicensis, 
Mangelia Trevelliana, Chemnitzia fulvocincta, Trochus milli- 
granus, Puncturella Noachina, Lucina flexuosa, and Cardium 
punctatum. Of the rarer species met with in less abundance, 
the following may be noticed, Mangelia brachystoma, M. teres, 
Natica Greenlandica, Hulimella Scilla, Philine quadrata, Cyli- 
chna strigella, Pecten striatus, Crenella decussata, and Nera 
brevirostris. 
The large number of small species recorded in the third column 
is in part due to the fact that a quantity of the sand and mud 
obtained in Berwick Bay was taken home for examination. 
This I have subsequently searched with much care, and have 
thus added many species to the list which were unobserved on 
board. <A careful examination of some parts of the Dogger 
Bank siftings, had, however, convinced us that it was not worth 
carrying home, and I have no doubt, that the genera Odostomia, 
Rissoa, Chemnitzia, and Eulimella are much more abundant in 
Berwick Bay than in the other localities which we dredged. 
