NOETH-WEST OE ENGLAND AND NOETH WALES. 



129 



they are. Complicated and inexplicable as the features of glacial 

 geology are when viewed separately, I have attempted to show that 

 there are recognizable features in common, running through all, that 

 point to geological agents in the past not very dissimilar to those 

 we now witness. Then as now, but from a more limited area pro- 

 portionally to the amount of submergence, the Thames, the Mersey, 

 and the Severn, and innumerable other streams and rivers, brought 

 down their quota of material to the beds then forming at the 

 bottom of the sea. 



APPENDIX. 



Report on the Sands and Gravels and Boidder-clays and the top 

 Silt, at the Bock F of the Atlantic Docks, Liverpool. By David 

 Robeetson, Esq., F.L.S., F.G.S. 



No. 1. Sand- and gravel-bed at the bottom of the section is the 

 most puzzling of the whole, as it contains a few freshwater Ostra- 

 coda and numerous fragments of what appear to be marine shells, 

 but so small and waterworn that no character is left by which they 

 can be satisfactorily identified ; yet, from various peculiarities of the 

 fragments, I have little or no doubt that they are marine. It is, 

 however, singular that no Poraminifera were detected in it, or- 

 ganisms that are in most cases present in marine deposits, even 

 where no other animal remains are to be seen. 



The material consists, in round numbers, of 70 per cent, of fine 

 sand, with very little mud, and 30 per cent, of gravel. Many of 

 the pieces are distinctly striated and well rounded and polished. 



No. 2. The reddish-brown clay of this parcel consists of 60 per 

 cent, of fine mud, 32 sand, and 8 of gravel ; about one half of both 

 sand and gravel is more or less angular ; the other half is well 

 rounded, and one piece in particular finely striated. Shell-frag- 

 ments are numerous, but all so small and imperfect that they 

 cannot be identified. The following are the Poraminifera : — 



Biloculina ringens, Lamk. 

 Triloculina oblonga, Mont. 

 Quinqueloculina semirmlum, Linn. 

 Lagena sulcata, W. 8c J. 



marginata, W. 8c J. 



globosa, Mont. 



squamosa, Mout. 



hexagona, Will. 



Lagena melo, If Orb. 

 Polymorph ina communis, If Orb. 

 Bulimina pupoicles, If Orb. 

 Cassidulina crassa, If Orb. 

 Truncatulina lobatula, Walker. 

 Polystomella striato-punctata. 



F.$M. 

 Nonionina depressula, W. 8c J. 



It is unusual to find so many Poraminifera and no Ostracoda or 

 other marine animal remains. 



No. 3. Red muddy sand much waterworn. The organic remains 

 are represented by very small chips of shells, a fragment of a star- 

 fish, and one Poraminifer {Nonionina depressula). 



No. 4. Red clay, consisting of 58 per cent, of fine mud, 20 of 

 sand, and 22 of gravel. No satisfactory striations were detected on 

 any of the pieces, which were mostly small and waterworn. Shell- 

 fragments moderately common. It is rather remarkable that these 



