256 DREDGING REPORT, 1862. 
dition as to lead to the belief that they are derived from a post- 
pliocene bed, situated in Berwick Bay, about 25 miles from that 
town, in 40 to 50 fathoms water, a supposition confirmed by the 
fact that they have not been recorded as living inhabitants of our 
seas. ‘These are 
Murex ermaceus. 
Margarita cinerea. 
Mya Uddevallensis. 
Astarte elliptica. 
Saxicava sulcata. 
In addition to these the following species were met with in 
the same locality, dead, and in such condition and in numbers so 
disproportionate to those found living, that it seems safe to 
conclude that they too exist in, although they do not exclusively 
belong to, the post-pliocene bed referred to, viz: — 
Trophon clathratus. 
Mangelia linearis. 
Trevelliana. 
turricula. 
Natica mtida. 
Trichotropis borealis. 
Chenmitzia fulvocincta. 
Turritella communis. 
Rissoa cimiciordes. 
Trochus 
Emarginula reticulata. 
Puncturella Noachina. 
Arca tetragona. 
Venus casina. 
Mya truncata. 
Further to show the subarctic relations as regards present 
distribution, and glacial affinities as regards geological time, of 
the shells obtained, the former are distinguished in the list thus 
(*) and the latter thus (ft). We find-that of the 138 species 
in our list 32 are now living in Greenland, and 54 are met with 
in the glacial beds of these islands. For purposes of comparison 
