﻿Lasanius 



Lanarkia 



Birkenia 



Thelodus 



Lasanius 



Cyathaspis 



Tremat- 

 aspis 



Nautiloid 

 (Gompho- 

 ceras) 



Lampshell 



(Spirifer) 



Hemiaspis 



Chonetes 



Sea-urchin 

 (Palaeechi- 

 nus) 



Staurocephalus 

 SILURIAN ^MARINE LIFE 



Deiphon 

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