'318 Reviews — A. J. Jukes-Broime — 



as coral T'eefs. With a party of Glasgow geologists I visited one of 

 the localities on the Solway last summer in consequence of a vigorous 

 discussion on this question, and in comparison with various living 

 coral reefs I felt bound to regard the limestones there as entitled to 

 the name of fossil coral reefs. The question is no doubt largely 

 a matter of definition, and Mr. Jukes-Browne's definition of a coral 

 reef seems too exacting. The question is important, as Palaeozoic 

 reef-building corals like those of modern seas seem to have been 

 limited to warm and shallow waters. 



The chapter on the Old lied Sandstone gives a judicious summary 

 of the various theories of its formation. Mr. Jukes-Browne now 

 accepts the evidence of an actual land barrier along the Bristol 

 Channel, which separated the Old Bed Sandstone lake of South 

 Wales from the Devonian Sea. He does not refer to recent 

 arguments in favour of the marine origin of the Scottish Old 

 Bed Sandstone, and his most important proposals in this chapter 

 are the reduction in number of the lakes proposed by Sir A. Geikie. 

 It seems to the writer, however, that this is a step in the wrong- 

 direction, as the subdivision of the lakes is realty required. The 

 deposits are different from those of large lakes ; and at least for 

 some areas the most satisfactory explanation of the Old Bed 

 Sandstone seems to be that it was formed as widespread sheets 

 of gravel and sand on the flood plains of shallow, inconstant rivers. 

 These rivers would doubtless have widened here and there into 

 lakes ; and when they were cut off from the rivers and their waters 

 evaporated, all their fish would have been deposited in a crowded 

 fish bed. The abundance in some layers of pebbles with wind- worn 

 shapes indicates the exposure of the shingle to sand erosion while 

 lying on the stony flats. 



The author maintains the view that the Chalk was deposited in 

 a deeper sea than some recent authors have allowed it, and for at 

 least some zones of the Chalk Mr. Jukes-Browne's conclusions seem 

 most probable. 



In his account of the glacial deposits the author calls attention to 

 the fact that the word ' kame ' is the Scottish for an esker. That 

 question of nomenclature will have to be considered and settled. The 

 term kame has been largely adopted abroad with quite a different 

 meaning, so that the Scottish kames are not kames according to the 

 foreign acceptance of the term. The greatest convenience of the 

 greatest number would be secured by accepting kame for fluvio- 

 glacial hummocks, although that course may be etyrnologically and 

 historically incorrect. 



The results of the author's study of the succession of English earth 

 movements have a useful bearing on many questions of wide general 

 interest. Thus he has recognized movements in the Midlands which 

 have greatly affected the growth of our present river system. He 

 dismisses Professor Davis' views, without much discussion, except on 

 special points, as when upholding the greater influence of marine as 

 compared with subaerial denudation in planing off the top of the 

 Wealden anticline. Mr. Jukes-Browne recognizes that the rivers of 

 South-Eastern England must once have arisen in the Welsh highlands, 



