280 



ME. J. S. G.WRDXER OX THE LEAP-BEDS 



steel-grey clay (7i), at the base of which the most interesting* leaf-bed 

 of all is met with. This consists for an inch or two of layer upon 

 layer of leaves in the most perfect preservation, and retaining 

 almost the colour of the dead leaves themselves. One of the most 

 striking, as well as most abundant, is Ginkgo, of large size and 

 purple colour. Still more conspicuous is the large PlaUmites liebri- 

 dicus, Forbes, one leaf exposed measuring full 15| inches in length 



Fig. 6. — Leaf-bed and Gravels at Ardtun. (Scale about 30 feet 



to 1 inch.) 



a. Columnar basalt, 40 feet. 



b. Position of first leaf-bed, obscured by grass, about 2 feet. 



a. Gravel, varying from about 25 feet to a maximum of nearly 40 feet. 



d. Black or second leaf-bed, 2\ feet. 



e. Gravel, about 7 feet. 



f. Grey Clay, 2 feet. 



g. 6 inches laminated sandstone, with 3 inches of fine limestone with leaves 



at base. 



h. Clay, with leaves at base, 1 foot. 



i. Chinch, with rootlets, 7 inches. 



j. Amorphous basalt, becoming columnar at base, about GO feet. 



and 10| in breadth. Many other kinds of leaf appeared to be 

 almost equally fine, and the characteristic dicotyledonous trees of 

 this locality possessed at that period relatively large foliage. In 

 the same bed were coniferous branches like the living Taxodium 

 (Glyplostrobus) Tieterojohyllum and Ceplialotaxus. Unfortunately, 

 every effort to remove and preserve these specimens has failed. 

 There are rush -like stems, from 1 to 3 inches in diameter towards the 

 base, but the beds are almost destitute of monocotyledons, and no trace 

 of Ferns or even of Equiseta has been seen in them. This lowest leaf- 

 bed passes into a thin seam of coal in one direction, and rests upon 

 6 to 9 inches of whitish, clunchy, and concretionary clay (i), with 

 rootlets, and with softer clay filling in the rough surface of the 

 underlying basalt (j). 



