Carboniferous Limestone, Llantrisant. 69 
The dolomite yielded— 
Caninia cornucopia. 
Syringothyris cuspidata. 
S. laminosa (very common), 
(3) In a quarry near Hendy Farm, along the road from Miskin to 
Pontyclun (exposure ¢), encrinital dolomite and massive oolite are 
observed. 
Fauna. 
Cyathophyllum o. 
Productus corrugatus, var. 
Syringothyris cuspidata. 
S. laminosa. 
Athyris ingens, de Kon. (= Athyris ct. glabistria, mut. C-S). 
(4) Along the road, north of Miskin, which joins the main road 
from, Llantrisant to Cardiff, there are two quarries, to left and right 
of the road respectively. 
In the first of these (exposure @) the ascending succession is as 
follows :— 
Encrinital dolomite and oolite. 
Thin-bedded black limestone (‘ china-stone ’). 
Massive oolite. 
Blue and grey well-bedded limestone. 
The dolomite at the base contains the same fossils as exposure ¢ 
near Hendy Farm. 
The upper beds contain— 
Lithostrotion Martini. 
Productus corrugato-hemisphericus. 
Seminula ficoides (abundant). 
The second quarry (exposure ¢) lies to the north of the last, and 
about 100 yards distant. 
The oolitic hmestone here contains— 
_ Productus cf. corrugatus | 
Prod. corrugato-hemisphericus - All abundant. 
Seminula ficoides J 
As has been previously noticed, a variant of Prod. corrugato - 
hemisphericus approaches close in form to Prod. striatus. 
Ia. Correlation of the Limestone East of Llantrisant with the Avonian 
of the South-West Province. 
The exposures described above fall readily into the following 
positions on the zonal scale :— 
: § S.= Exposure e. 
SERN Lake (8, =Exposure d (top of quarry only). 
fae Wxposure ¢ and bottom of Exposure d. 
Caninia-zone ee of C, (y) = Exposure 6. 
Zaphrentis-zone (pars) = Exposure a. 
II. Exposures West of Llantrisant Station, near Llanharry. 
There are several quarries in 8, and Lower D on the left of the 
road from Bryn-Sadler to Llanharry. 
(1) Im a quarry some half-mile south-west of Llanharry Station. 
