124 SILURIAN GROUP. 



5. Upper Slate of f "• ^''"'^"i'^ ^^'^ "^^ ""^ flagstoBes. 



Kendal i *" ^'^^^ ^°^ slates with Upper Ludlow fossils. 



I a. Coarse slates passing downwards into 4 rf. 



4. Ireleth Slates. . 



' d. Coarse slates, flags and grits. — Terehratula 

 navicula, and other Lower Ludlow fossils. 

 c. Upper Ireleth slates. 

 h. Calcareous slates and limestone. 

 a. Lower Ireleth slates. 



% CoTiiston frit / Graptolithus Ludensis, Cardiola interrupta, 

 Orthoceras Ibex. 



2. Coniston Brathay r Graptolithus Ludensis, and Upper Silurian 

 Flagstone. "^ species. 



1. Coniston Limestone and Slate . . . Lower Silurian fossils. 



The fossil organic remains of this period are very in- 

 teresting, as they make us acquainted with some of the 

 early forms of life on the surface of the globe. In the 

 Lower Silurian, Trilobites and some species of Brachiopoda 

 appear to have been abundant, associated with MoEusca, 

 Corals, and Crinoidea ; in the Upper beds, Corals become 

 more abundant, as well as various orders of marine Mol- 

 lusca, Brachiopoda, and Crinoidea, occurring with them, 

 and a few remains of Sauroid fish. 



LIST OF PUBLICATIONS, &c. 



Bo\vman, J. E., ' On the Silurian Rocks to the West of Ahergele,' 

 Geol. Trans, vol. vi. 



Trans. Manchester Geol. Soc. vol. i. p. 194. 



Lyell, C, ' Elements of Geology' vol. ii. 



' On the Silurian Strata,' &c., Geol. Proc. vol. iii. p. 463. 



Mc'Coy, F., ' Synopsis of the Silurian Fossils of Ireland.' 



