C. Lapivorth — Classification of the Lower Palaeozoic Books. 15 



study of the Lower Palaeozoics, our suggestion may be tolerated now, 

 and adopted later on, when the necessity for this course has become 

 more strikingly apparent. To those who interest themselves in the 

 attempted correlation of the Lower Palaeozoic Bocks of the Northern 

 Hemisphere, and who are continually hampered by the want of some 

 clear and unmistakable generic terms expressive of the general 

 parallelism among these widely- separated deposits, the ease and 

 comfort of a classification which imitates Nature herself in placing 

 the three grand members of the Lower Palseozoic Eocks upon an 

 equal footing, is an advantage of which they are certain in time to 

 avail themselves to the full. Those again, who feel how vain is the 

 endeavour to parallel the special formations and minor stages of our 

 British Lower Palaeozoics with those of other areas, will hail with some 

 approach to satisfaction the release of such convenient sub-generic 

 tei-ms as Loioer and Upper Cambrian, and Lower^ Middle, and Upper 

 Silurian, with the list completed by the addition of Loioer and Upper 

 Ordovician; — terms all of easy and immediate application, and all 

 expressive of epochs, which, so far as our present knowledge enables 

 us to judge, embrace tolerably equal periods of geological time. 



No earnest student of the history of discovery among the Lower 

 Palaeozoic Eocks, whose opinions are the natural outcome of his own 

 careful generalization of presently known facts, and not the petrified 

 remains of the views he so enthusiastically adopted a quarter of a 

 century ago, can fail to perceive that the ideas of the extreme party 

 which claims all the Lower Palaeozoics for the Silurian are fated soon 

 to become wholly extinct. The wave of backward opinion which 

 led this party to revert in substance to the ideas of their predecessors 

 was inevitable. We are now witnessing the as-inevitable return of 

 the tide. Here and there this application of the term may linger on 

 for a time, as in Bohemia, and possibly in Scandinavia, kept alive 

 by the very principle that must in the end prove fatal to it, when 

 local conveniences become superseded by cosmopolitan necessities. 



A single glance at the magnificent development of the Lower 

 Palaeozoics on the continent of North America is enough to convince 

 every unbiassed investigator how much we have yet to learn 

 regarding their British prototypes, and how ridiculously inadequate 

 is our present estimate of their grand importance in the geological 

 series. As this knowledge dawns upon us as the result of our 

 discoveries in the future, some such classification as is here pro- 

 posed will perforce be adopted by all; and the systematist will then 

 be left free to work out his generalizations untrammelled by the 

 defects of a cramped and unnatural nomenclature. Our British 

 strata can in the end return but one answer to the most extended 

 appeal. Every geologist will at last be driven to the same con- 

 clusion that Nature has distributed our Lower Palaeozoic Eocks in 

 three sub-equal systems, and that history, circumstance, and geologic 

 convenience, have so arranged matters that the title here proposed 

 for the central system is the only one possible. 



