1873.] BRYCE — JURASSIC ROCKS OF SKYE AND RAASAY. 333 



overlain by ordinary trap. In the trap-tuff are imbedded a vast 

 number of small pieces of altered, apparently fully mineralized 

 wood, of which I procured a few specimens, in the hope of having 

 the species of wood determined by slicing. The tufa dies out 

 gradually westwards, and the ordinary trap succeeds. 



No account of the Skye traps is attempted in this paper ; the 

 subject is too wide, and requires much careful study of the wild 

 and difficult cliff-sections. Some general remarks on the relations 

 of these various strata to one another, and to the intercalated traps, 

 are reserved till an account has been given of the beds in Raasay. 



A section of similar estuarine beds occurs at Vaterstein, already 

 mentioned as the most westerly point where the Jurassic beds 

 appear. 



The following are the beds in descending order : — 



Section IX. The Vaterstein Beds. 



1. Shales and thin limestones, with Paludina scotica, Cyrena Cunningliami, 



fish, and thin sheets of basalt. 



2. Shell-beds, Ostrea hebridica and Cyrencs. 



3. Shell limestones, marbles, Cyrence; shales and marls. 



4. Sandy beds and marls, fossils few and obscure. 



Total thickness about 120 feet. 



Section of upper part (descending) : — 



1. Basalt. ft. in. 



2. Altered shales and earthy limestones, fish-remains 3 7 



3. Basalt 3 1 



4. Earthy limestone , 5 : -4 



5. Blue hydraulic limestone, white on weathered face 5-7 



6. Earthy limestone 4 



7. Finely laminated black shales, fish and Cyrena Cunningliami... 1 9 



8. Paludinal marl and limestone (P. scotica) 1 4 



9. Basalt 1 



10. Shale i 3 



11. Basalt 10 



12. Shale. 



Fossils: — Cyrena Cunningliami, Ostrea hebridica (7=0. multiformis, Koch 

 and Dunker), Melania inermis, Paludina Scotica ; fish the same as at Loch Bay. 



Raasay. 

 The Jurassic strata occupy a much larger area in this island than 

 on the coast of Skye opposite. The great mass of the central part 

 of the island is formed of them ; and they descend to the east coast 

 in lofty mural precipices, through a distance of 7 or 8 miles ; cross- 

 ing the island south-west in a narrow band, they occupy a small 

 area on the south coast, and on the west coast emerge at the sea- 

 level from under the overlying rocks. At a short distance inland 

 from this point they appear in a deep river-cutting, and in a small 

 tract continuous with it, from which the overlying rocks have been 

 swept away. At their north and south terminations on the east 

 coast, and at the point on the west coast where they are visible, 

 these strata rest on the unconformable bods of the Torridon or Cam- 

 brian Sandstone, which is continuous across the whole island along 

 the north frontier of these beds, and occupies a small area in the 



VOL. XXIX. r-ART I. Z 



