Pahvozoic Rocks of Sweden. 277 



from the older terminology, at once consistent with what is fair and 

 suited to the circumstances in general. 



In the first place we must set down that in proportion as the 

 geological researches into our Palaeozoic formations have advanced the 

 old conviction that the latter in our country form a connected whole, 

 the various parts of which are not divided by sharp limits, has become 

 a certainty. However, for faunistic reasons it seems advisable to 

 divide the formations in question into three groups, in the main 

 corresponding to Barrande's three Silurian faunas. It is no less for 

 the formations considered as a whole than for the various groups that 

 we must establish appellations. 



Before entering upon this we must touch, however briefly, upon 

 a very debated question of priority, viz. the name Silurian or Cambrian. 

 In our opinion it is the more bootless to enter into details, as no one 

 is likely to assert that either Murchison or Sedgwick were really fully 

 cognizant of what it was that they stamped with the respective names. 

 That any dispute about the line between the different systems could 

 arise at all is due, of course, to the fact that the authors themselves 

 did not recognize with certainty coeval formations where these in any 

 degree showed varying development. That Murchison's Caradoc was 

 the same as Sedgwick's Bala, was a point on which both were equally in 

 the dark, even if Sedgwick, as it soon appeared, saw that this was the 

 case, at least as far as certain strata were concerned. That Murchison's 

 stratigraphical mistakes, which considerably increased the chaos, did 

 not bring him great distinction, goes without saying, but on the whole 

 we must not forget that palseontological science at that time, when, for 

 instance, the graptolites and their stratigraphical significance were still 

 practically unknown, was insufficient to determine with certainty the 

 stratigraphical succession when the strata were not in a relatively 

 undisturbed position. That both Murchison and Sedgwick added so 

 much to our knowledge of these older Palaeozoic strata, that the names 

 given by them must by no means be condemned by reason of the flaws 

 which were inherent in them, and which, we may say, were bound to 

 exist in them, is beyond all doubt. But the manner in which these 

 names should be used, or, in other words, the establishment of the 

 range of their meaning, must concern a period which will have made 

 a real limitation of the idea possible. 



To return to the question of what appellations we are to select, our 

 first business is to see what names can be used as a collective appellation 

 for these formations. Among the likeliest of these we may mention 

 especially Transition System, Cambro- Silurian, and Silurian. Of 

 these, for reasons we need not repeat here. Transition System is very 

 unsuitable. The same is true of Cambro-Silurian, especially as 

 Sedgwick himself proposed this name in 1843 for all strata from the 

 Bala, inclusive, to the base of the Wenlock, a proposal which, how- 

 ever, he afterwards (1854) withdrew. On the other hand, the name 

 Silurian seems to be quite suitable, not only because the range of 

 the word corresponds with Murchison's latest claims, but because it 

 has often been used, as we pointed out above, as a collective name. 

 But if it is to he used as such it must, of course, not be admitted as 

 a group name. Since, for obvious reasons, we retain the names 



