Structure of the Eastern Alps. 395 



Ft. In. 



7. Green and yellow arenaceous and micaceous marl ; containing geodes, and 



concretions of hydrate of iron g 



8. Green, unctuous marlSj separated by thin bands of ferruginous marlstone .. 7 



9. Highest bed of shell-limestone, of porous structure, of rusty brown colour, 



and full of Cerithia 1 



10. Yellow ochrous coarse-grained limestone : it contains many Trochi and 



other shells, and is burnt for lime 4 6 



11. White limestone, stained by brecclated fragments of greenish marlstone: it 



contains many Cerithia and other shells ; some in good preservation .... 1 2 



12. Coarse, brown limestone, with shells 1 o 



13. Fine-grained, strong-bedded, white limestone, with shells on the surfaces of 



the bed. It splits up into slabs from six inches to a foot thick, and is used 



in ornamental architecture 4 5 



14. Limestone, nearly resembling the preceding j 3 



15. Green, blue, and yellow unctuous marl 2 6 



'16. White, shelly limestone 1 g 



1 7. Rough, shelly, ochrous bed of porous structure 9 



18. Sandy bed, obscured by water at the bottom of the quarry 36 ii 



Geodes and concretions of hydrate of iron (similar to those in No. 7.) occur 

 in all the ferruginous sandy beds^ and are also found in the sandy strata under 

 the limestone. 



The preceding group is of considerable, economical importance ; but its 

 chief geological interest arises from its fossils. Among those we obtained 

 from it are the following : — 



Solen. 



Cardium — three species. 



Pullastra. 



Saxicava rugosa ? London-clay and crag. Min. Con. Tab. cccckvi. 



Venus or Cytherea. 



Mytilus Brardii. Mayence. Fauj. Ann. du Mus. tome 8, pi. Iviii. fig. 1 \, 12. 



Cerithium vulgatu7n; C. pictwn (Bast.) ; C. plicatum (Bast.). 



Trochus — some specimens of which are not to be distinguished from an un- 

 described recent species from the Pacific^ in the possession of Mr. G. Sowerby. 

 It abounds in the Hartberg limestone. 



Turritella incrassata. Crag. Min. Con. Tab. li. fig". 6. 



3. Section in a direction nearly South and North from Radkersherg to Rie- 

 gisburg, showing the Structure of the Youngest Tertiary Groups of Styria, 

 and their Relations to a Series of Volcanic Rocks *. 



For some miles to the north of Radkersberg, a broad plain of gravel and 



* Plate XXXVI. fig. 15. 



3e2 



