PROCEEIHNGS OF THE SCIENTIFIC SOCIETIES OF LOTsDolN-. 283 



is, in fact, the true old Boulder-clay of the geologists of the West 

 of Scotland. The Shells are entirely confined to a bed of clay of 

 open texture, containing a few small stones ; it rests immediately on 

 the Boulder-clay as above defined, and is succeeded by various drift- 

 beds consisting of seams of clay and sand intermingled, containing 

 stones that are rarely striated, and without Shells. 



Dr. Bryce then discussed the probable origin of these drifts, and 

 the amount of depression which the land had sustained before the 

 Shell-bed was deposited over the Boulder-clay, which he considered 

 to have been formed by land-ice emanating from central snow-fields, 

 and covering the whole surface of the country. 



3. " On the Occurrence of Beds in the "West of Scotland in the 

 position of the English Crag." By James Bryce^ M.A., LL.D., 

 r.G.S. — In consequence of the results arrived at from the investi- 

 gation of the Drift-beds of Arran, Dr. Bryce determined to examine 

 all the recorded cases of fossils occurring in the Boulder-clay, the 

 Chapel Hall case having, however, been already undertaken by the 

 Eev. H. W. Crosskey. The most celebrated case is that of the 

 occurrence of Elephant-remains at Kilmaurs, near Kilmarnock, in- 

 Ayrshire ; and the author showed, from a section of the quarry 

 exposed for the purpose by Mr. Turner, of Dean Castle, which cor- 

 responded exactly with one already furnished to him by an aged 

 quarryman, that the Elephant-remains, the Eeindeer's horn, and the 

 Shells, all occurred in beds below the Boulder-clay, and not in that 

 deposit, as has always been stated. The same conclusion was 

 arrived at respecting the occurrence of Elephant-remains at Airdrie 

 and Bishopbriggs, and of Eeindeer's horn with Shells at Croftamie ; 

 and the author concluded by discussing the question whether the 

 fossils belong to the Upper Crag period, or merely indicate a down- 

 ward extension of the Arctic fauna which characterizes the beds 

 directly above the Boulder-clay, as described in the last paper. 



4. " On the Tellina proxima bed at Chapel Hall, near Airdrie." 

 By the Eev. H. W. Crosskey. Communicated by Dr. Bryce, E.Gr.S. 

 — One of the most perplexing cases in Scotland, upon any theory of 

 the formation of Boulder-clay, has been the alleged occurrence at 

 Chapel Hall of a clay-bed containing Tellina proxima intercalated 

 between two masses of true Boulder-clay. The Shells were first 

 found by Mr. James Eussell in sinking a well ; and the case was 

 made known by Mr. Smith, of Jordan Hill, in a paper laid before the 

 Geological Society in 1850. At the author's request Mr. Eussell 



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