Miss M. M. Ogilvie— Coral id the ''Dolomites:' 3 



summer and winter among the rough winding paths and dilapidated 

 huts, content to lead their cows and mow their hay. In the wider 

 valleys the sun ripens hearty crops twice a year, and life flows on 

 pleasantly, after a lazy Italian fashion. The barrenness of the 

 dolomite mountain is such that even chamois rarely frequent their 

 clefts and terraced table-lands ; snow caps most of them during nine 

 months out of the twelve, and is perpetual on the highest summits. 



With the exception of a few scattered remnants of Jurassic and 

 Cretaceous rock, the geological age of the deposits exposed through- 

 out this country is Triassic. We are concerned with the history of 

 Triassic deposit in South Tyrol, in the midst of which, we are told, 

 there came a long epoch of Coral growth and reef-building. If this 

 be true, the data of the geologist have a keen interest both for the 

 geographer and the zoologist, whose duty it is to compare these fossil 

 Coral Reefs with reefs now growing, and find corroboration or the 

 reverse for the various theories which have been advanced regarding 

 the growth of recent Coral Reefs. The chief data which geology 

 determines, are the exact nature of the sedimentary rocks, the order 

 in which they succeed one another, the fossil remains which they 

 contain, and any particulars regarding the manner of occurrence of 

 the fossils. That seems a simple enough commission, and yet in 

 practice it is often very hai'd to execute, no part of it more hard 

 in the Alps than that of determining the order in which the I'ocks 

 succeed one another. For the sediments which were deposited by 

 the great basins of water in Triassic time have since been folded 

 and twisted and raised into entirely new positions in relation to one 

 another. So that a rock which was once below is now alongside or 

 even above its neighbour — or its fossils have been destroyed, or a 

 volcanic invasion has taken place ; in fact, endless accidents may 

 have happened since Triassic time, and it requires much time and 

 patience to unravel the mysteries introduced into a once simple 

 succession. In a word, to be a good ancient geographer of the Trias, 

 one must first be a wary stratigraphist. 



We shall begin by quoting the succession of Triassic rocks in 

 South Tyrol and the interpretation of it given by Mojsisovics ^ : — 



Eh^tic Beds. 

 Dachstein dolomite. 

 Raibl marls, sandstones, dolomite. 

 Coral f ^''^^^i'^'^ Dolomite"! thinning into TCassian marls and limestones, 

 j^j, -^ Wengen ,, I contemp. 4 TVengen shales and volcanic ash. 



[Buchenstein ,, j deposits of (^Buchenstein limestones and ashy rocks. 

 Muschelkalk (Alpine) limestone or dolomite. 

 "Werfen shales and thin bedded sandy limestones. 

 Permian Bock:. 

 The actual part which these rocks take in the landscape may 

 be briefly described. The so-called " Coral Reefs " rise as sheer 

 precipices 2000-8000 feet high, or dwindle to nothing. The gaunt 

 form of their cliffs is unbroken by familiar planes of bedding. 

 Eaibl marls draw themselves as a narrow band above them, and 



"■ E. Mojsisovics v. Mojsvar, "Die Dolomit-Biffe von Siid Tirol und Venetien," 

 Wien, 1879. 



