222 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



Silurian System" in some cases where the evidence adduced by him- 

 self pointed, as it appears to me, by a true logical inference, to some 

 modification in the naming of the groups. Thus he continues to de- 

 signate the May Hill grits by the name Caradoc sandstone, though 

 their fossils are almost identical with those of the Wenlock beds. In 

 describing the Usk district he has indeed changed the nomenclature 

 and elevated certain beds, previously called Caradoc and Llandeilo, 

 into the Wenlock period ; and after having done this he adds — 

 " that here (in the Usk district) is a second instance, more re- 

 markable than that already established on the western side of the 

 Malvern Hills, of the deposition of sandstones, miaeralogically of the 

 Caradoc type, in an ocean filled with the life of the Wenlock 

 period." (Memoir, p. 202.) 



Fig. 4. — Biagram showing a vertical section of the Lower Palceozoic 

 Rocks in the Malverns. (After Phillips ; Memoir, p. 51*.) 



Old Red Sandstone, 13. 





{ 









Downton sandstone 



Ludlow shales (upper) . 

 Aymestry rock 



Ludlow shales (lower). . . 



— 



l2 

 11 

 10 



9 



8 



7 



6 

 5 



4 



3 

 2 



1 





P 



1000 feet. 





BJ 







■{ 





Woolhope limestone . . . 



v^. — - ----- — 







^^:;- 



2000 feet. 









Caradoc conglomerate. . . 

 Traps 



•;;::.•::'■••■■•.•;;■;•••■- 



fcff; 







3000 feet 











^%m 









4000 feet 



Syenite. 

 If the fact be admitted, that certain beds (at May Hill and the 

 Malverns), " although mineralogically of the Caradoc type," contain 



* In accordance with the views of this paper, we should call Nos. 4 and 5 by 

 the names May Hill conglomerate and May Hill sandstone. 



