230 



nate deposits of gypsum and rauchwacke ; and its great masses of 

 compact and subcrystalline limestone, sometimes containing innume- 

 rable Hippurites, &c. &c. They show that the higher part of the 

 series is often made up of inclined and contorted beds of compact 

 limestone, indurated shale, calcareous sandstone, &c. &c. containing 

 Ammonites and Belemnites ; that the system here and there passes 

 into a true green-sand with the characteristic fossils of that forma- 

 tion ; that a granular iron ore is worked in this part of the series at 

 Sonthofen not distinguishable from some of the ferruginous green- 

 sands of Kent ; that iron ore occurs in the same system south of 

 Bregenz, associated with a nummulite-limestone and thick beds of 

 shale. Finally, they state, that they found no great masses of 

 conglomerate subordinate to this group. It is, however, here 

 and there succeeded and surmounted by enormous masses of alter- 

 nating sandstone and conglomerate; which (as they graduate into 

 beds containing tertiary fossils) are considered as the true base of 

 the tertiary system. 



7. Tertiary deposits. — The authors having described these deposits 

 of the Austrian Alps in former papers, only return to the subject for 

 the purpose of noticing some remarks which have appeared in the- 

 recent publications of Dr. Boue. 



1. Dr. Boue is mistaken in supposing that they confounded the 

 iron sand of Sonthofen with rocks of the tertiary age. It was 

 described by them as containing Ammonites and Belemnites, and 

 as alternating with beds of the newer Alpine limestone * ; and 

 they are surprised that Dr. B. persists without any grounds in at- 

 tributing to them a contrary opinion. 



2. Dr. Boue states that the tertiary formation of Haring is en- 

 tirely of freshwater origin. The authors prove that it contains se- 

 veral species of marine shells ; from which they conclude (contrary 

 to the opinion of Dr. B.) that the marine tertiary formations of the 

 Alps do sometimes ascend far up the transverse, secondary valleys. 



3. Dr. Boue maintains that the tertiary formations on the flanks 

 of the Austrian Alps commence with the superior division of that 

 great class of rocks. The authors on the other hand have shown 

 by other transverse sections and suites of fossils, that some of the 

 inferior groups of the tertiary deposits in the Gratz basin are of the 

 age of the London clay. So far they consider that there is a differ- 

 ence between themselves and Dr. Boue on questions of fact. 



4>. They also differ from that author on questions of opinion. — 

 The overlying deposits of Gosau, and in some of the lateral valleys of 

 the Traun. were considered from their fossils as of an age newer than 

 the chalk. He, on the contrary, identifies them with the lower green- 

 sand. But the Gosau beds are unconformable to, and do not 

 appear to form any part of the system of newer Alpine limestone or 

 green-sand, &c. ; and they appear to be identical with certain de- 

 posits on the outskirts of the Alps, which are associated with the 

 tertiary series. They are not interlaced with the secondary system, 



* See Annals, Jan. 1830, p. 53. 



