LOWER LIAS: DUNRAVEN. 115 
band, suggesting a local change in conditions, should be grouped 
rather with the overlying than with the underlying beds, and hence 
we need not hesitate to place it and the Button Stone also in the 
Lower Lias. Moreover the "Guinea-bed" (as mentioned p. 151). 
appears to be a remanie* bed, containing Lower Lias as well as 
Rheetic fossils, and therefore of the age of the later remains. 
From the Lower Lias here, I obtained Ostrea irregularis, and 
poor specimens, identified somewhat doubtfully with Ammonite* 
Jolmstoni and Pholadomya glabra. Moore recorded Am. plan- 
orbis, Lima gigantea, L. tuberculata, Ostrea multicostata (arietis), 
and Pecten Pollux (suttonensis).* These fossils compare well with 
the beds at Sutton and Southerndown. 
Blue Lias Lime (for building-purposes, &c.) is now made from 
the shaly limestones of the Lower Lias ; and Carboniferous Lime- 
stone is brought for the preparation of " white lime" (for 
agricultural purposes). 
The ordinary beds of Lower Lias above the Southerndown 
Series at Dunraven, have yielded the following species : 
f Ammonites arigulatus. 
f Bucklandi. 
f Conybearei. 
f laqueolus ? 
semicostatus. 
Belemnites acutus. 
Cerithium. 
fTurritella (cast). 
fGryphsea arcuata. 
Lima duplicata. 
gigantea. 
Hermanni. 
f Ostrea multicostata (arietis). 
fPholadomya ambigua. 
f glabra. 
fUnicardium cardioides. 
Rhynchonella calcicosta. 
Pentacrinus tuberculatus. 
From Dunraven onwards to Aberthaw, the coavst is bounded by 
cliffs exhibiting the blue and brown argillaceous limestones, 
shales, and marls that overlie the conglomeratic Lias of Southern- 
down. On the east side of the Dunraven headland, the con- 
glomeratic beds dip away beneath the beach, being repeated for 
a short distance by the oblique fault (before mentioned, p. 107), 
und by another fault a little further on : beyond which they are 
not again seen along the coast-sections. 
These cliffs exhibit, perhaps, the finest exposure of the Lower 
Lias Limestones in this country. We have not the complete 
sequence of Lias visible at Lyme Regis; but here in South 
Wales the zones of Ammonites angulatus and A. Bucldandi 
(taken together) are much more fully and continuously exposed. 
It is true that 14 miles of cliffs, showing the same set of beds, 
dislocated here and there by faults, seem a little monotonous ; and 
as fossils are neither very varied nor very abundant, we cannot 
wonder that the cliffs for the greater part of the distance are but 
little visited by the geologist. The beds must attain a thickness of 
quite 200 feet, and for great part of the way the limestones stand 
out also in ledges and platforms along the foreshore, so that our 
progress along these natural pavements is a very happy one, 
* Quart. Journ. Geol. Soc., vol. xxiii. p. 520. 
f Species obtained by myself, and identified by Messrs. Sharman and Newton : 
some of these and other species are recorded by Moore. 
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