Bihliographical Notices. 157 



with. Our acquaintance is enlarged now with the great and old Lau- 

 rentian formations of Canada, thanks to the Geological Survey of that 

 country, and with synchronous rocks in Scotland, Bohemia, and else- 

 where, as worked out by Giimbel, Murchison himself, and others — 

 with far more of the so-called " Primordial" fauna of the Lingulella- 

 flags and the corresponding beds in Bohemia than formerly known, 

 thanks to Barrande, Salter, Hicks, and others — with a clearer view 

 of the Caradoc-Bala series and its intercalated volcanic masses, 

 thanks to our Geological Survey — with improved notions respecting 

 the Middle and Upper Silurian rocks and fossils, thanks to Salter, 

 Davidson, and many others — and so forth. The clearing up of the 

 doubt as to the real geological place of Telerpeton Elginense,Hypero- 

 dapeton, and Staganolepis, of the upper Sandstones near Elgin, now 

 determined to be Triassic, is a great gain. The clear notices of the 

 nature and relations of the palaeozoic rocks of the Pentlands and of 

 Ayrshire, by Mr. Geikie, are also highly acceptable ; and the more 

 exact knowledge of the Palaeozoic rocks of the Continent, from the 

 communications of De Prado, Collomb, De Yemeuil, Kjerulf, Dahll, 

 Barrande, Helmersen, and others — and of those of Canada and 

 America also, by Logan, Hall, Billings, Bigsby, &c., add greatly to 

 the value of this edition. 



'^ Lastly," writes Sir Eoderick, " after taking a general view of 

 the history of the diiFerent races of animals which have succeeded to 

 each other during all geological periods, I have, in the last chapter, 

 added a brief sketch of my long-cherished convictions respecting 

 many of the former physical and mechanical changes of the earth's 

 surface, as contrasted with any movements which have taken place 

 in historical times ;" and well does he argue respecting the great 

 changes the young earth suffered, as proved by the long and deep 

 fractures, extensive dislocations, enormous reversals of crumpled 

 strata, and vast removals of shattered rocks, that such great move- 

 ments and denudations are inexplicable by reference to the modern 

 action of common earthquakes, volcanoes, rain-wash, and wave- 

 action ; and he refers rather to such mighty operations as we have 

 been lately reminded of by the powerful earthquake-wave of Hawaii, 

 rolling in, 60 feet high, for a quarter of a mile, and answering, with 

 its fatal bore, the devastating eruption of Mauna Loa. 



Although these two great chiefs among geologists, Murchison and 

 Lyell, differ in opinion as to whether the progressive advance of 

 organic nature has been at a relatively slow or rapid rate, and whe- 

 ther the changes of land and sea, and all the concomitant variations 

 of physical conditions, have taken place violently or gently, in long 

 past periods, these are matters that little concern the actual truths 

 of geology and the application of geological knowledge to the mani- 

 fold requirements of our age. To the advance of the science and to 

 its practical use each of these noble works is an admirable contribu- 

 tion and aid. 



Both of the eminent geologists above mentioned are veterans, 

 fellow-workers forty years ago, when their science was young. 



