1865.] Geology and Palaeontology. 679 



preservatives of no less than six different periods, one of which is 

 Pre-glacial, three are Glacial, and two Post-glacial. 



Of the Pre-glacial period there are traces only. The first of the 

 Glacial periods is that of " Land-ice," during which the rocky sur- 

 face of the country was scratched and polished, and the Boulder-earth 

 was accumulated ; the second is the " Period of Depression," during 

 which the Glacial-marine beds, containing Arctic shells, and the 

 stratified beds occurring at high levels were deposited ; the third is 

 that occupied by the " Emergence of the Land," during which the 

 glaciers finally retreated, and the Valley-gravels, Moraines,^ and Sub- 

 marine Forest-beds were deposited. The close of this period is 

 properly Post-glacial, and Mr. Jamieson considers the submarine 

 forest beds to fall into this latter category. 



The first of the true Post glacial periods is termed by the author 

 the " Second Period of Depression," and within its limits the 

 Estuarine beds and raised beaches of Scotland were deposited ; the 

 former are of very great extent, and constitute the well-known Carse- 

 lands of the Forth and Tay (including the Carse of Gowrie — the 

 Garden of Scotland) ; in them, also, the first traces of man in Scot- 

 land have been discovered. The second and last period is that during 

 which the land was elevated to its present position, and the blown 

 sand, beds of peat, and shell-mounds were accumulated. 



Concerning the date of this last change, Mr. Jamieson has nothing 

 new to say, which is a very great pity, as the question is now in 

 anything but a satisfactory condition ; he states, however, that 

 artificially chipped flints occur on the surface of some of the mounds, 

 the bases of which are not more than four feet above the sea-level, 

 and strewed on the rolled pebbles of the beaches of the last period, 

 and it seems to us that this evidence is rather against Mr. Geikie's 

 inference that the last elevation of Scotland was posterior to the 

 Eoman invasion ; but Mr. Jamieson is inclined to be of a different 

 opinion. 



In an Appendix the author gives classified lists of the shells found 

 in the different localites and deposits, with their present distribution ; 

 these lists and the paper altogether are indispensable to every student 

 of Post-tertiary Geology, whether of Scotland or any other country. 



Dr. Bryce's paper " On the Drift-beds of Arran " is a correction 

 of the Bev. E. B. Watson's statement, that the Arctic shells discovered 

 by him occurred in the Boulder-clay. Dr. Bryce, like other geologists 

 of the West of Scotland, is of opinion that the Boulder-clay proper 

 has not hitherto furnished any fossils ; and he examined these Arran 

 Drifts for the purpose of ascertaining whether Dr. Watson's shells 

 really occurred in the Boulder-clay, or on the horizon in which 

 they have been found in Clydesdale, namely, immediately above that 

 deposit. As the result of his researches, Dr. Bryce states that the 

 Arran shells occur in a bed of clay, immediately above the Boulder- 

 clay, and beneath another series of beds, without fossils, which he 

 terms " Upper Drifts." In Clydesdale a bed of laminated clay divides 

 the Shell-bed from the Boulder- clay, the shells are better preserved 

 than in Arran, and shells of British species occur in the " Upper 



