Mollitsks. 5705 



The investigations, on which these papers are based, were made by 

 me during the year 1851, which I spent upon the Isle of Cumbrae, in 

 the very centre of the district named, and during which I thoroughly 

 examined the sea all round its shores. In the early spring of 1855 I 

 was, for a week or two, on the Isle of Arran, for the purpose of 

 dredging in Lamlash Bay and hunting up the shore. 



This paper will, however, be much indebted to the labours of 

 others. The Clyde has had accurate and active observers, who have 

 examined almost all parts of it most carefully, and who, living on its 

 shores, and having ample opportunities and appliances for its inves- 

 tigation, have devoted much of their time, and that too, most success- 

 fully, to the study of its inhabitants. In the eighth volume of the 

 1 Memoirs of the Wernerian Society,' published in the year 1838, 

 there appeared a paper, " On the last changes in the relative levels of 

 Land and Sea in the British Islands, by James Smith, Esq., of Jor- 

 danhill, F.R.S.L. & E., F.G.S. & M.W.S.:" this paper contains a 

 " Catalogue of Recent Shells in the Basin of the Clyde and the North 

 Coast of Ireland," to which I shall make frequent reference. Mr. 

 Smith added from the Clyde many most interesting shells to the 

 British Fauna ; among these may be mentioned Pectus danicus and 

 striatus, Pilidium fulvum, Propilidium Alcyloide, Puncturella Noa- 

 china, Trichotropis borealis(?) and Mangelia Leufroyi. No year 

 passes without his yacht skimming the surface of the Clyde, while his 

 dredge brings him into communication with the ground beneath. 

 Mr. Smith is, however, even better known as a geologist than as a 

 conchologist, and his researches into the recent beds of the Clyde are 

 of great interest. In the following catalogue I have affixed an 

 asterisk to those shells which Mr. Smith has found fossil in the 

 " Newer Pliocene Deposits " of the Clyde : under this name of 

 "Newer Pliocene," Mr. Smith has included two deposits, — the first, 

 a few feet only above the present sea level, does not contain any 

 fossils, except of such shells as are still to be found recent in 

 the Clyde; the second, at a somewhat higher level and underlying 

 the last- mentioned, abounds in fossils embedded in a stiff clay, 

 the majority of which are still to be found living in the neighbouring- 

 sea ; but a few, though still extant in more northern places, are 

 no longer to be met with as denizens of the waters of the Firth 

 of Clyde. These deposits are frequently spoken of by Forbes and 

 Hanley as the " Pleistocene," or " Glacial Beds " of the Clyde. 



At Saltcoats there lately lived an eager, acute, and energetic natu- 

 XV. 3 A 



