INK OKDOVICIAN sy.s'i KM 



115 



Acltn. 



Crustacea. 



Bryozoa. 



Vxsils of tlic 



.s 



Favosites crus-.i, .Munticulipora tibrosa, Nebulipora 

 ^ lens, Lyopora favosa, Halysites catriiularius. 



dimaoograptni Wilsoni, Dicranograptus Clingani, 

 I'lnirograptiis linearis, Dicellograptus anceps, D. 

 oomplanafeu, 1). truncatus, Leptograptus flaccidu.-. 



Rhaphanocrinus basal is. BohincpiuBmaanuititiin,8pluB- 

 nmitrs iiiiinitiis. S. Litrlii, Ilfiiiii-osuiitcs rugatus. 



Agiiostus trinodus, Trinucleus concentricus, T. seticornis, 

 Illaenus Davisi, I. Bo\\ niaiiui, Homalonotus bisul- 

 catus, rii.ico|K apiculatus, P. Brongniarti, Lie-has 

 laxatus, L. hibernicus, Stauroceplialus globiceps. 



Monticulipora favulosa, M. petropolitana, Phyllopora 

 ri, Rainipora hochstellaris. 





I-'ii;. SO. THREK B.M.A l> 



ftraehiopoda. 



Orthis actonise, 0. flabelluluni, 0. calligrainma, 0. 



liii'orata, 0. liirnantensis, 0. vespertilio, Lcpueua 



(Plectambonite.s) sericea, Strophomena expansa, S. 



siluriana, Treniatis corona. 

 Lam r :llibranchia. Ctenodonta varicosa, Paliearca ediiKindiilbrmis, Modo- 



lopsis obliqua, M. expansa, M. inodiolaris. 

 Koloj>ea concinna, Cyclonema crebristria, Murcliisonia 



simplex, Ecculioinjilialus Bucklandi, TfUtm-ulito 



anglicus, Hyolithes (Theca) triangularis, Bellerophon 



nod(us. 

 (Jyrtoceras sonax, Orthoceras vagans, Trochoceras cor- 



nuarietis. 



Gastropoda. 



Cephalopoda. 



C. BRITISH ORDOVICIAX ROCKS 



Ordovician rocks occupy much larger areas of the surface in 

 Great Britain than the Cambrian rocks, and are also found in 

 several parts of Ireland. In Wales they occupy nearly all tin- 

 western and central portions of the country, outside the Cambrian 

 outcrops. They pass eastward beneath the overlying Silurian 

 .strata, and portions of them emerge again in Shropshire and 

 Radnorshire. 



