1 8 GEOLOGICAL BIOLOGY. 



Conybeare and Phillips' s Perfection of the Weraerian System. 

 The form which the geological scale assumed in English 

 geological systems is seen typically in Conybeare and Phillips's 

 Geology of England and Wales (1822). Arranged in order 

 from above downwards, it is as follows : 



I. Superior order. (Neues Floetzgebirge of Werner.) 

 II. Supermedial order. (Floetzegebirge of Werner.) 



(1) Chalk formation. 



(2) Ferruginous sands. 



(3) Oolitic system or series. 



/ N ( Red marie or New Red sandstone. 



{ Newer Magnesian or conglomerate limestone. 

 III. Medial, or Carboniferous order. 



(1) Coal-measures. 



(2) Millstone, grit and shales. 



(3) Mountain limestone. 



(4) Old Red sandstone. 



De la Beche. De la Beche* carried out the system more 

 completely, calling the first, or superior order, Supercretaceous 

 group, and applying the terms Cretaceous, Oolitic, and Red 

 sandstone to three groups into which he divided the second 

 order, and giving the third the name Carboniferous group. 

 Below these he recognized Werner's Grauwacke group, for 

 what was the lower part of the original Uebergangsgebirge of 

 his earlier classification, and below this were the inferior 

 stratified or non-fossiliferous rocks, and the unstratified rocks. 

 All of the names, it will be observed, are names indicative 

 of mineral characters. 



Maclure's Application of the System to American Rocks. If 

 we turn back to the year 1817 we find the same Wernerian 

 system applied to the classification of North American rocks 

 by William Mackire.f The author writes : " Necessity dic- 

 tates the adoption of some system so far as respects the clas- 

 sification and arrangement of names. The Wernerian seems 

 to be the most suitable, first, because it is the most perfect 

 and extensive in its general outlines; and secondly, the 



* "A Geological Manual," 3d edition, 1833. 



f "Observations on the Geology of the United States of America," Phila- 

 delphia, 1817. 



