236 REPORT—1904. 
west of Rhymney (51° 45’ 35” N., 3° 18’ 5” W.), thereis a thin clayband 
ironstone which contains in great abundance— 
? Scaldia minuta or Estheria. Naiadites ? 
This band should form a good index-bed. 
Lower down on the same patchworks, near the horizon of the Elled 
Coal, south of Brynpwllog (51° 45’ 45” N., 3° 18’ 0” W.) were found :— 
Anthracomya modiolaris (common). Carbonicola acuta. 
From the roof of the Ras Las Coal, No. 2 Pit, Fochrhiw, the following 
were obtained :— 
Carbonicola aquilina (common). Naiadites modiolaris. 
Naiadites carinata 5 
From the patchwork near Dowlais (51° 45’ 35’ N., 3° 20’ 15” W.), at 
the horizon of the 9-foot coal, the following were collected :— 
Anthracomya modiolaris. Naiadites carinata (common). 
Carbonicola aquilina (common). 
The Ras Las Coal has been regarded as identical with the 9-foot coal, 
and the above lists support this correlation. 
At a level near Hirwaun (51° 45/5" N., 3° 31/5" W.), about the horizon 
of the Cnapiog Coal, fine specimens of Carbonicola robusta were abundant. 
In the roof-shale of a thin coal (4 inches thick) which occurs above the 
grit overlying the engine coal, where it outcrops south of Clydach Colliery, 
the following plant remains were found :— 
In an exposure of black shales in the W. bank of R. Rhymney, a few 
yards north of Blaen Rhymney, were found— 
Anthracomya pumila. Beyrichia arcuata. 
Carbonicola acuta (numerous). Celacanthus lepturus. 
Naiadites modiolaris. 
These black shales are in the so-called Millstone Grit Series. 
In dark shales in the same series of rocks a horizon, about 15 inches 
thick, is exposed in the banks of the stream 8. of Garth (51° 46’ 15” N., 
3° 20' 65’ W.), and contains— 
Carbonicola acuta (abundant). Carbonia sp. 
A little higher in the series and farther up the stream to the east, in 
dark shales, about 2 feet thick, the following list was obtained :— 
Solenomya primaeva. Edmondia sp. 
Ctenodonta laevirostris. Lingula mytiloides. 
Nucula aequalis. 
Higher again in the series, near Pitwellt Pond (51° 46’ 45” N 
”? 
3° 20’ 30’’ W.), another marine bed was seen, yielding— 
Lingula mytiloides. Posidoniella laevis. 
Quarries opposite Clydach on 8. side of R. Clydach showed the follow- 
ing sequence in the Carboniferous Limestone .— 
1. Blue limestone in thick beds, with thin black shales intervening. 
2. Purple and green marl with calcareous nodules, 15 feet thick. 
3. White limestone, oolitic and very pure. 
—s 
