THE FOSSIL FLORA OF THE SOUTH WALES COAL FIELD. 



569 



IV. General Section of the Eastern portion of the Coalfield. 



Depth 



in 

 Yards. 



Name of Seam. 



Thickness. 



Depth 



in 

 Yards. 



Name of Seam. 



Thickness. 



77 

 170 

 208 



Upper Pennant Series. 



No. 1 Llantwit, ... 

 No. 2 do. ... 

 Llantwit Four Feet, or 

 Mynyddislwyn, 



Ft. in. 



8 

 6 



4 6 



929 

 941 

 948 

 956 

 961 

 963 

 979 



1013 



Wliite Ash Series — contd. 



Soap Vein Ironstone, 



9 Feet Seam, 



Dirty or Bute, ... 



Trigloin, 



2 Yard Coal, ... 



7 Feet, 



No. 3 Yard, 



Gellideg, Lower 4 ft. or Old Coal, 



Alternations of Shales and Seams 

 of Ironstone for 30 to 40 

 yards. About 4 Feet of iron- 

 stone in all. 



Garw Seam, or Bottom Vein, 



Ft. in. 



8J 

 8 

 4 5 



2 



4 6 



5 5 



3 



4 



1 8 



263 

 492 

 543 

 552 

 613 

 654 

 714 

 752 

 757 



Lower Pennant Series. 



Pencoedcae or Stinking Vein, 



No. 1 Ehondda,... 



Fforest Vach, 



No. 2 Ehondda,... 



No. 3 do. ... 



Havod Vein, 



Abergorchy Vein, 



Pentre Vein, 



Gorllwyn Vach,* 



4 



3 

 2 10 



4 

 4 



2 10 



3 

 2 9 

 2 





Farewell Rock. 

 = Millstone Grit. 





784 



846 

 859 

 869 

 881 

 890 

 902 

 908 



White Ask Series. 

 Gorllwyn, 



Cockshot Eocks about 60 yards. 

 Three Coals, 

 2 Ft. 9 In. Coal, 

 Eider Coal, 

 4 Feet Seam, 

 No. 1 Yard, 

 6 Feet Seam, 

 Eed Coal, or Engine Vein, 



2 



3 6 



2 9 



1 8 



4 9 



2 9 

 8 6 

 2 9 





Carboniferous or Mountain Lime- 

 stone. 







Lower Limestone Shale. 







Old Red Sandstone. 







Silurian. 





* The strata above this are almost exclusively hard sandstone, locally called " Pennant Sandstone." 



Little has previously been done in working up the Fossil Flora of the South Wales 

 Coal Field. The only papers dealing with this subject, as far as I am aware, are by Sir 

 William Logan " On the characters of the Beds of Clay immediately beneath the Coal 

 Seams of South Wales, and on the occurrence of Boulders of Coal in the Pennant Grit of 

 that District," # in which some now well recognised facts respecting the occurrence of 

 Stigmaria in the Underclays and their relation to the overlying Coal Seams were first 

 pointed out. 



In the " Iron Ores of South Wales," t a few species of fossil plants are noted, but some 

 of the identifications are open to doubt. 



In 1884 Dr Stur contributed "Some notes on a small collection of Fossil Plants from the 

 neighbourhood of Llanelly and Swansea." J His fossils came from certain beds, the lowest 

 of which was the " Bushy Vein," which is situated in the Upper Pennant Series. A collec- 

 tion from the Cwmbach Pit, near Swansea, contained the following species : — 



* Trans. Geol. Soc. London, 2nd ser., vol. vi., 1842, p. 491. 



t Mem. Geol. Survey Gt. Brit., " Iron Ores of Great Britain," part iii., 1861. 



X Verhandl. d. K. K. Geol. Reichsanstalt, 1884, No. 7, p. 135. 



