Structure of the Eastern Alps. 397 



d. Greenish, calcareous sandstone, with various casts of shells. 



e. Micaceous, thick-bedded, calcareous sandstone, of bluish and greenish colours. 



/. Sandy, micaceous, yellow niarlstonc with casts of a Venericardia ; Cerithium picttim ; a 

 Modiola, of the same species with one found at Sixt-Miihle ; a Pecten ; a Mactra ; a Turbo (?) • 

 a Trochus ; Nummulitcs vuriolariaij); and some other shells similar to those at Radkersberg. 



g. Marl, and thinly foliated sandy beds. 



h. Yellowish limestone, with casts of shells. 



i. Green and white sand. 



A:, White, sandy, micaceous marl, with calcareous concretions, and many bivalve shells which 

 fall to pieces on being touched. 



I. Finely laminated, sandy marlstone, blue, white, and iron. stained ; with casts of shells. 



m. Brown and blue, micaceous, argillaceous grit. 



fi. Bands of light-coloured, calcareous and micaceous sand. 



o. Sandy marls. 



p. Micaceous and calcareous sandstone, with traces of carbonized wood and plants, passing up- 

 wards into a conglomerate. 



q. Indurated conglomerate, and micaceous calc-grit, forming the summit of the second terrace 

 which is obscured by vegetation. 



The base of the third and highest terrace is made up, to a considerable 

 thickness, of very micaceous sand, containing some pebbles. It is imperfectly 

 exposed ; but near some high vineyards, the sandy beds are cut through in 

 several places for the extraction of a fine-grained, perfect oolite, which is 

 quarried here, at Wasen, and at Preesing ; and has been extensively used in 

 the construction of the neighbouring churches and other public buildings. It 

 is an irregular, concretionary rock, formed in the midst of the calcareous sands, 

 marls, and conglomerates ; its thickness is consequently variable. In the Pop- 

 pendorf quarries, the beds of the best building-stone are from four to six feet 

 thick; and their structure is so truly oolitic, that the most experienced geolo- 

 list on seeing them in hand specimens, or the hewn stone of a building, might 

 confound them with the great oolite of Bath. In the quarries, he would how- 

 ever be soon undeceived by finding casts of Cerithia, and other tertiary shells 

 on the surfaces of the coarser and exterior beds. Amongst the oolitic grains 

 of the coarser beds, and sometimes within them, are minute fragments of 

 bivalves: in the same beds also several species of univalves; for example, a 

 Cerithium, a Murex, a depressed shell resembling a Planorbis, a Natica or 

 Nerita, a Turritella, a Turbo, &c. 



Some of the spherules are hollow, but others are arranged about grains of 

 semi-crystalline calcareous matter, or particles of sand. The beds of true 

 oolite are overlaid by irregular, concretionary masses, partially oolitic, which 

 alternate with unctuous sandy marls. Some of these concretions are amor- 

 phous; some assume contorted tubular forms; others are finely laminated. 



