part 1] THE WESTPHALIA!^, ETC. Or EAST GLAMORGAIS'. 61 



in the Six-Foot and Two-Foot Nine Seams, extremely rare in the 

 Pentre and Abergorky Seams, more numerous in the No. 3 Rhondda 

 Seam, and still more frequent in the No. 2 Rhondda Seam. 



Seeds (probably belonging to Cordaites). — Not present at the 

 three lowest horizons and the No. 2 Rhondda Seam. Very weakly 

 represented at the remaining six horizons : namely, from the Nine- 

 Foot to the No. 3 Rhondda Seam. 



The Different Classes of Plants as a Whole. 



Eqtjisetaxes. — Rather abundant in the Five-Foot Seam and 

 dominating the other classes in the Middle Yard Seam. In the 

 Upper Yard Seam the distribution is similar to that of the Five- 

 Foot Seam. They are again dominant in the Nine-Foot Seam, 

 appearing still numerous in the Six-Foot Seam, scanty in the Two- 

 Foot Nine Seam, considerably stronger in the Pentre Seam, and 

 for the third time they easily dominate the other classes in the 

 Abergorky Seam, and maintain a very strong position in the No. 3 

 Rhondda Seam. In the No. 2 Rhondda Seam, they predominate 

 over the other plants for the fourth time by a narrow margin. 



Sphenophyllales. See Sphenophyllum. 



Lycopodiales. — Particularly scanty in the Five-Foot and 

 Middle Yard Seams, increasing in the Upper Yard Seam, gradually 

 weakening in the Nine-Foot and Six-Foot Seams, dominant at two 

 horizons in succession (namely, the Two-Foot Nine and Pentre 

 Seams), and disappearing in the Abergorky, No. 3 Rhondda, and 

 No. 2 Rhondda Seams. 



Ferns and Fernlike Plants. —Wide distribution in the Five- 

 Foot and Middle Yard Seams, dominant in the Upper Yard Seam, 

 with a good representation in the Nine-Foot Seam. They become 

 dominant in the Six-Foot Seam. These plants suddenly disappear 

 in the Two-Foot Nine, Pentre, and Abergorky Seams, but are 

 conspicuous and become dominant for the third time in the No. 3 

 Rhondda Seam, maintaining a strong position in the No. 2 Rhondda 

 Seam. 



Cordaitales. — Dominant in the Five-Foot Seam, and well 

 represented throughout the nine succeeding horizons, with the ex- 

 ception of one weak point of distribution found in the Middle 

 Yard Seam. 



The following list of species embodies («), those species which 

 are common to the Westphalian and Staffordian Series ; (J), those 

 belonging to the Westphalian only ; and (c), those belonging to 

 the Staftordian only. I am deeply indebted to Dr. R. Kidston, 

 F.R.S., and to Dr. F. L. Kitchin, M.A., for the determination 

 of the species of plants in my collection. 



