PERMIAN. 211 



From this two-fold arrangement of the rocks in Germany, 

 the term Dyas was proposed in 1859 by Jules Marcou ; and 

 many authorities at the present day prefer this term to that of 

 Permian. 



Fossils are abundant in the Magnesian Limestone and Marl 

 Slate : they include the Brachiopoda and Mollusca Camarophoria 

 crumena, C. globulina, Terebratula elongata, Lingula Credneri, 

 Sirophalosia Goldfussi, S. lamellosa, Sifep/orhytichus pelargonatus , 

 Athyris pectinife7-a. Product us horridus, Spirifera alata, S. Urei, 

 Spiriferina multiplicata, JSIonotis {Avicula) speluncularia, Schizodus 

 (Axmus) obscurus, Bakavdlia antiqua, Pleurophorus cosfatus. Turbo 

 Mancuniensis , and Chiton. Few Cephalopods occur. The Polyzoa 

 include Acanthodadia (^Glauconome) anceps, Synodadia virgulacea, 

 and Fenestdla retiformis ; and the Fishes Platvsomus strialus, 

 Pygopterus mandibulan's, Dorypterus, CcpJacattthus, Palceoniscus degans, 

 P. comptus, and other species — hence the term Paloeoniscian 

 applied to the series by Phillips ; there also occur Proterosaurus, 

 the oldest known Lacertilian Reptile, and Lepidotosaunis, one of 

 the Labyrinthodonts. The plants Voltzia and C aider piles are re- 

 corded from the Lower Permian Sandstone. The flora, which may 

 include Sigillaria, Alethopteris, and Neuropteris, is perhaps allied 

 to that of the Coal-measures ; but Mr. Carruthers has observed 

 that the Permian vegetation also possesses Mesozoic afiinities, and 

 in fact that the commencement of the Mesozoic flora is to be sought 

 in the Permian. As before mentioned, the evidence of the Plant- 

 remains must be received with caution. 



The genera Produdus, Sirophalosia, Spirifera, Camarophoria, 

 Streptorhynchus, Athyris, and Fenestella, although not exclusively 

 Palaeozoic, are yet links that strongly bind the Permian fauna with 

 that of the Carboniferous period which preceded it.^ 



]\Ir. J. W. Kirkby has stated that in the Magnesian Limestone at Hampole 

 (or Hampall), near Uoncaster, " in but a quarter of an ounce of limestone I have 

 picked out 298 separate organisms, the majority being specimens of Turbo 

 /lelichius. Another experiment of a like kind, the quantity of limestone being 

 the same, yielded even more astonishing results. From it 1 extracted 461 

 specimens of T. helicimis, iS of TurriteUa Altenhurgensis, 7 o{ Rissoa Leighi, 2 of 

 Terebratula elongala, I oi Bairdia plebeia, 24 of Miliola pusilla, and 8 fragments of 

 Stetiopora Mackrothi ; in all 513 organisms."^ 



Some beds in the Lower Magnesian Limestone of South Yorkshire, at Brods- 

 worth, Cadeby, etc, are almost wholly composed of fragments of Polyzoa. 



The Magnesian Limestone, which is the most important member 

 of the Permian series, may be compared with the Muschelkalk ; for 

 although occupying a diff'erent horizon, both beds belong to the 

 same system, and both are locally developed ; the former being 

 present only in Nottinghamshire and the northern counties of 

 England, and the latter being absent from this country. The 

 Magnesian Limestone comprises several beds diff"ering much in 



' J. W. Kirkby, Q. J. xvi. 415. See also Prof. W. King, Permian Fossils 

 (Palreontograph Soc.) ; R. Howse, Catalogue of Permian Fossils, 1848. 

 2 Q. J. xvii. 292, 313. 



