Ch. XXII.] TNFRA-LIASSIC STRATA OF AUSTRIAN ALPS. 



435 



several memoirs on the rocks in question, has favored me with the 

 following summary of the order of succession of the Hallstadt beds 

 in the Austrian Alps, which I had an opportunity, when travelling in 

 the autumn of 1856, of verifying in company with Mr. Giimbel, of 

 Munich. 



The uppermost strata first enumerated immediately underlie the 

 Lower Lias of the Swabian Jura. This lias is represented near 

 Vienna by a brown limestone, containing Ammonites Bucklandi, A. 

 Conybearii, &c. 



Strata below the Lias in the Austrian Alps, in Descending Order. 



1. Koessen beds. 



(Synonyms, Upper St. _, 

 Cassian beds of Escher 

 and Merian.) 



2, Dachstein beds. 



Hallstadt beds 

 (or St. Cassian). 



A. Guttenstein beds. 



B. "Werfen beds, base 

 of Upper Trias ? 



Lower Trias of some 

 geologists. 



f Gray and black limestone, with calcareous marls hav- 

 ing a thickness of about 50 feet. Among the 

 fossils, Brachiopoda very numerous ; some few 

 species common to the genuine Lias ; many pecu- 

 liar. Avicula contorta, Pecien Valo?iiensis, Car- 

 dium Jihceticum, Avicula incequivalvis, JSpirifer 

 Ilicnsteri, Dav. Strata containing the above fos- 

 sils alternate with the Dachstein beds, lying next 

 below. 



White or grayish limestone, often in beds 3 or 4 feet 

 thick. Total thickness of the formation above 

 2000 feet. Upper part fossiliferous, with some 

 strata composed of corals. (Lithodendron.) Lower 

 portion without fossils. Among the characteristic 

 shells are Hemicardium Widferii, Megalodon tri- 

 queter, and other large bivalves. 



Red, pink, or white marble, from 800 to 1000 feet in 

 thickness, containing more than 800 species of ma- 

 rine fossils, for the most part mollusca. Many spe- 

 cies of Orthoceras. True Ammonites, besides 

 Ceratites and Goniatites, Belemnites (rare), Por- 

 cettia, Pleurotomaria, Trochus, Monoiis salinaria, 

 &c. 



A. Black and gray limestone 

 150 feet thick, alternating 

 with the underlying Wer- 

 fen beds. 



B. Red and green shale and 

 sandstone, with Salt and 

 Gypsum. 



Among the fossils are 

 Ceratites cassianus, 

 Myacites fassaen- 

 sis, JSTaticella cos- 

 tata, &c. 



In regard to the age of the rocks above mentioned, the Koessen 

 and Dachstein beds have been referred by some to the Lias, by others 

 to the Trias, while many have considered them to be of intermediate 

 date. But Mr. Suess has shown that the Koessen beds correspond to 

 the upper bone-bed of Swabia, in which the Microlestes was found 

 (see p. 432), and the same geologist remarks that some of the fossils 

 of the beds 1 and 2 are identical with the Irish " Portrush beds " of 

 General Portlock, described in his Report on Londonderry. The 

 Koessen beds have been traced for 100 geographical miles from near 

 Geneva to the environs of Vienna. 



The German geologists are now generally agreed, as already stated, 

 that the Hallstadt and St. Cassian beds are of the age of the lower 



