SILURIAN SYSTKM 



159 



Fig. 48. OROUP OF WENLOCK F068IL8. 



<i. Acer vularia luxurious. ^trophonella euclypha. 



b. Omphyma subturbinatuni. /. Spirifer plicatellus. 



. Atrypa reticularis. ;/. Horiostomn ilisoont. 



'/. Lepttena rhomboidalis. h. Cyathophyllum truncatum. 



i. Araclmophyllum MurchisonL 



The following are some of the other fossils which are specially 

 characteristic of each of the three Silurian series or divisions : 



Hydrozoa. 

 Aclinozoa. 



Fossils of the Llandovcry and Valentian Series 



(See table of graptolite zones.) 



Lindstrcemia bina, Land, subduplicata, Pinacopora 

 Grayi. 



