THE TRIASSIC PERIOD. 203 



(7) ' Monograph of the Permian Fossils of England' (Palaeontographical 



Society). King. 



(8) 'Monograph of the Permian Brachiopoda of Britain' (Palaeonto- 



graphical Society). Davidson. 



(9) "On the Permian Rocks of the North-West of England and their 



Extension into Scotland" 'Quart. Journ. Geol. Soc.,' vol. xx. 

 Murchison and Harkness. 



(10) ' Catalogue of the Fossils of the Permian System of the Counties of 



Northumberland and Durham.' Howse. 

 (n) ' Petrefacta Germanise.' Goldfuss. 



(12) ' Beitrage zur Petrefaktenkunde. ' Miinster. 



(13) ' Ein Beitrag zur Palseontologie des Deutschen Zechsteingebirges.' 



Von Schauroth. 



(14) ' Saurier aus dem Kupfer-schiefer der Zechstein-formation.' Von 



Meyer. 



(15) 'Manual of Palaeontology.' Owen. 



(16) ' Recherches sur les Poissons Fossiles.' Agassiz. 



(17) * Ichnology of Annandale.' Sir William Jardine. 



(18) 'Die Fossile Flora der Permischen Formation.' Gceppert. 



(19) 'Genera et Species Plantarum Fossilium.' Unger. 



(20) " On the Red Rocks of England of older Date than the Trias" 



'Quart. Journ. Geol. Soc.,' vol. xxvii. Ramsay. 



CHAPTER XV. 

 THE TRIASSIC PERIOD. 



We come now to the consideration of the great Mesozoic, or 

 Secondary series of formations, consisting, in ascending order, 

 of the Triassic, Jurassic, and Cretaceous systems. The Trias- 

 sic group forms the base of the Mesozoic series, and corre- 

 sponds with the higher portion of the New Red Sandstone of 

 the older geologists. Like the Permian rocks, and as implied 

 by its name, the Trias* admits of a subdivision into three 

 groups a Lower, Middle, and Upper Trias. Of these sub- 

 divisions the middle one is wanting in Britain ; and all have 

 received German names, being more largely and typically de- 

 veloped in Germany than in any other country. Thus, the 

 Lower Trias is known as the Bunter Sandstein ; the Middle 

 Trias is called the Muschelkalk ; and the Upper Trias is known 

 as the Keuper. 



I. The lowest division of the Trias is known as the Bunter 

 Sandstein (the Gres bigarre of the French), from the generally 

 variegated colours of the beds which compose it (German, 

 bunt, variegated). The Bunter Sandstein of the continent of 

 Europe consists of red and white sandstones, with red clays, 



