nN) 
WD 
ADVERTISEMENT. 
Hypozoic rocks. 
(1) Older Cambrian groups inferior to the Bala limestone. 
(2) Upper Cambrian groups based on the Bala limestone. 
Caradoc group. It has perhaps no distinct representative in Scotland and the North 
of England. In Wales and Shropshire, it often overlies the Cambrian rocks 
unconformably, and there forms the physical basis of all the upper Silurian 
groups, while Paleontologically it connects itself with the Cambrian rocks. 
Upper Silurian rocks—including all the groups from the upper part of the 
Wenlock Shale to the Tilestone. 
Old Red Sandstone, or Devonian, groups. 
Carboniferous groups. 
Permian groups, which end the Palzozoic series, and are immediately: followed 
by the Trias, or New Red Sandstone. = 
Cambrian rocks. 
Qi 
In concluding this Notice, | have to return my grateful thanks to the Syndics of 
the University Press for generously taking on themselves the expense of the -letter-press 
of this Part; which, after all the assistance thus given to me, has not been: ‘brought 
before the public without much anxiety, and a great personal cost. 
Campripce, May, 1851. ADAM SEDGWIGK, 
Woodwardian Professor. 
