174 



HISTORICAL PALAEONTOLOGY. 



from the fact that almost all the varied types of which it is 

 composed disappeared utterly before the close of the Carbon- 



Fig. 1 16. Corals of the Carboniferous Limestone, a. CyatJwphyllum paracida, show- 

 ing young corallites budded forth from the disc of the old one ; a', One of the corallites 

 of the same, seen in cross-section; b, Fragment of a mass of Lithostrotion irregulare ; 

 I', One of the corallites of the same, divided transversely ; c. Portion of the simple cylin- 

 drical coral of Amplexns coralloides ; c 1 ', Transverse section of the same species; d, 

 Zaphrentis vermicularis, showing the depression or " fossula " on one side of the cup ; 

 e. Fragment of a mass of Syrmgopora ramnlosa ; f, Fragment otCluetetes tnmidns ; /', 

 Portion of the surface of the same, enlarged. From the Carboniferous Limestone of 

 Britain and Belgium. (After Thomson, De Koninck, Milne-Edwards and Haime, and 

 the Author.) 



iferous period. In the first marine sediments of a calcareous 

 nature which succeeded to the Coal-measures (the magnesian 

 limestones of the Permian), the great group of the Rugose 

 corals, which flourished so largely throughout the Silurian, De- 

 vonian, and Carboniferous periods, is found to have all but 



