G. A. Lebour — Limits of the Yoredale Rocks. 543 



beds of the Carboniferous Series, 1 and the massive calcareous forma- 

 tion which sufficiently distinguishes the Scar Series to the south has 

 given place in the west of this county to a mere extension below of 

 the Yoredale Series above. In a sense it would be correct to say 

 that in Northumberland the Yoredale Series is the only part of the 

 Carboniferous Series below the Millstone-grit present, with the ex- 

 ception of the Calciferous Sandstone, or Tuedian, group. 



Blit only in a very limited sense would this be true. When Prof, 

 de Koninck, in receiving the Wollaston Gold Medal of the Geological 

 Society in February last, took occasion to state, or rather to imply 

 perhaps, that the faunas of the Carboniferous Limestone Series of the 

 North of England and of Scotland were identical with that of the 

 Calcaire de Vise (the uppermost of his three Belgian divisions), 2 

 he no doubt said so in this limited sense. Palseontologicaily there 

 is no break in the northernmost part of England between the 

 Scar and the Yoredale Series, but this only means that the circum- 

 stances of life and of deposition were in this region free from the 

 changes which in the south determined those groupings of Carboni- 

 ferous organisms which mark off into clear stages the Carboniferous 

 Limestone as a whole. These northern beds are not the Yoredales 

 alone, increased to an enormous thickness. They are the Yoredalespfots 

 the Scar Limestone, rendered indistinguishable by the geographical 

 features of their time. They as truly represent the Tournai and the 

 Dinant as they do the Vise division, although they may be homo- 

 taxeous with the last alone. The life conditions of Yise lasted in 

 Northumberland from the close of the Calciferous or Tuedian age to 

 the time of the Millstone-grit, or possibly to the beginning of the 

 Coal-measure Period. Thus it is that in that part of England the 

 Yoredales, the Scar Series, etc., are mere names without significance. 



"In fact," as Prof. Eamsay has so well said, " viewed as a whole, 

 the Carboniferous Series consists only of one great formation, pos- 

 sessing different lithological characters in different areas, these 

 having been ruled by circumstances dependent on whether the strata 

 were formed in deep, clear, open seas, or near land, or actually, as 

 in the case of the vegetable matter that forms the coals, on the land 

 itself." 3 



Since then no Yoredales proper and no Scar Limestones proper 

 can be shown to exist, as such, in the great Carboniferous Limestone 

 Series of Northumberland, and since no comprehensive name has 

 been given to the blending of these two divisions which forms the 

 link between the Yorkshire and the Scottish types of the series, and 

 which is developed to its fullest extent in Northumberland, some 

 special name denoting this series must sooner or later be coined. 

 May I venture to suggest " Bernician Series " as a suitable term 



1 Up to the present time, the well-marked foraninifer Saccammina Carteri, Brady, 

 is apparently limited to a bed in the Upper or Yoredale part of the series, viz. the 

 Four-fathom Limestone. 



2 Abstract of Proc. of the Geol. Soc. of London, No. 296, p. 2. 



3 Physical Geology and Geography of Great Britain, by A. C. Eamsay, LL.D., 

 F.E.S., 2nd edition, 1872, p. 76. 



