58 TRANSACTIONS L1VEEPOOL BIOLOGICAL SOCIETY. 



some yellow, some grey, some reddish, of various tints 

 from pink to ruddy brown, and others darker, of all 

 shades of brown and dark grey. It is curious how, even 

 in a composite deposit made up of many different con- 

 stituents, there is usually a prevailing tint ; for example, 

 the bottom at one spot, although composed of mud, sand, 

 nullipores, shells, and stones, is distinctly of a rich ruddy 

 brown tint. The importance of this presence of prevailing 

 colours in the various sub-marine deposits is obvious in 

 its bearing upon the colours and habits of animals. 

 . Sample bags of all the more important sub-marine 

 deposits we have come upon have been sent, at Sir 

 Archibald Geikie's request, to the Museum of the Geo- 

 logical Survey in Jermyn Street. They are being examined 

 there by Mr. Clement Eeid, F.G.S., who writes the follow- 

 ing preliminary note in regard to them : — 



" On comparing these samples with British deposits of 

 Tertiary date, one finds a marked difference in lithological 

 character. Dredgings from the Irish Sea, and also from 

 the North Sea, are characterised by a much coarser and 

 more gravelly texture than one would expect at such 

 depths — coarser, in fact, than one finds in Pliocene 

 deposits yielding a similar fauna, indicating similar or 

 even smaller depths. A glance at these dredgings shows 

 the reason for this, for they are largely composed of 

 unworn or little worn fragments of rock, often entirely 

 incrusted by organic growth. The stones evidently have 

 not been transported far by water, or they would be 

 well rounded, like the pebbles found in our Eocene beds. 

 The incrusting organisms show also that the fragments 

 have lain undisturbed on the sea-bed, yet they have often 

 been derived from far-distant sources. Though no Glacial 

 striae were observed, and no undoubted sub-fossil Arctic 

 shells have yet been found at these localities, yet there 



