part t 



PALAEOZOIC. 



Fig. 4.— General Section of the Malvern Hills. 

 (Prof. J. Phillips.) 



e. New Red .Sandstone (Poikilitic). c, Silurian. 



^. Lower Old Red Sandstone. d. Cambrian. 



a. Gneiss (Archasan). 



S early as the year 1756, the rock-formation.s were 

 divided by Lehman into Primitive and Secondary, 

 the former term being appHed to those rocks in 

 which no fossils had been found, and the latter term 

 to the fossiliferous strata. Later on, in 1795 or 

 1796, Werner introduced the term Transition for a class ot 

 rocks intermediate between these old groups.^ In those early 

 days the arrangement of the rocks was but imperfectly under- 

 stood. 



The term Palaeozoic (derived from Greek words signifying 

 'ancient life') was introduced in 1838 by Sedgwick, and is 

 now generally applied to the oldest stratified rocks that enter 

 into the composition of the earth's crust. They are, in fact, 

 the ' Primary ' rocks with which the Geologist has to deal ; 

 and although this latter term (introduced by Hutton) is less 

 frequently used, perhaps because we are unable to state 

 positively that the oldest rocks known to us were those first 

 formed, yet it is a simple and by no means inappropriate 

 term. 



No doubt the earliest rocks that appeared at the cooled 

 surface of the earth "In the beginning" were of a crystalline 

 nature : more we cannot say. The old notion that granite is 



^ Conybeare and Phillips, Outlines of the Geology of England and Wales, p. vi. 



