Rev. A. Irving — Triassic Deposits of the Alps. 497 



inclufled among the rocks called 'plutonic' as thej' are in Lyell's 

 Students' Elements.^ The inountaiu appears to be nothing more 

 than an ancient ' stratified cone,' in the sense in which this term is 

 used by the writer just referred to. 



It is on the margins of such districts as the Bozen volcanic region 

 that the deposits known as Verrucano are commonly met with. In 

 such a relation they occur (according to Giimbel) on Lake Lugano, 

 in the Biindener Alps, in Windgalle, in the Mont-Blanc group, in 

 Judicarien, in Val Lugana, near Cilly, and near Raibl. Since the above 

 observations on the structure of the Rittner Horn were made by the 

 writer two or three months ago, he has found the intimate relation in 

 which the ' porphyries ' are placed to the ash-deposits noticed by 

 von Hauer.^ The passage is worth quoting : " The oldest porphyries 

 present (in the Bozen district) are younger than the clay-slates 

 through which they have pushed their way, and upon the surfaces of 

 which they are spread out, while the latest reach no further forward 

 in time than the older Trias ; since the tuffs, which on the one 

 hand are placed in most intimate relation with the solid porphyries, 

 pass on the other hand without any definite limit into the con- 

 glomeratic and sandy rocks of the Lower Trias." These ' Lower 

 Triassic ' strata of von Hauer are, as we have seen above, the 

 strata referred by Giimbel to the age of the German Dyas, for the 

 most part. 



Transition Beds. — Of late the view has been propounded by 

 some German and Austrian writers that the lower portions of the 

 Werfener Schichten and the massive white limestone of Schwaz (in 

 the Inn Thai) on the northern side of the Alpine chain, as well as 

 the Grodner Schichten, the black ' Bellerophon Limestone ' of the 

 Puster Thai (abounding in Foraminifera), the Brockel Dolomite, 

 near Triente (rich in copper ore), on the southern side, should all be 

 regarded as belonging to the upper horizon of the Dyas or Post- 

 Carboniferous system. This view is controverted by Giimbel on the 

 ground that the oi'ganic remains found in them do not give them 

 " a pure Dyassic character, but very much more that of a transition 

 series from the Dyas to the Trias." This, he points out, is par- 

 ticularly the case with the plant-remains recently found in the 

 Grodner Sandstein at Neumarkt, near Bozen, and in the numerous 

 recently-discovered fauna of the Bellerophon-Limestone of the Puster 

 Thai. Of these remains the following are figured in his excellent 

 little handbook before referred to. 



a. Plant-Remains from the Alpine Bed and White Sandstones, and 

 the overlying Grey and Calcareous Strata at Neumarkt : — 



^thophyllum Fotterliamim, Mass. 



Voltzia reetibariensis, Mass., and V. Messalongi. 



V. Br'dckhiana, Heer, and V. vicetina, Mass. 



Carpolithes Hungaricus, Heer, and Carp, foveolatus, Heer. 



Baiera cUgitata, Heer. 



1 Third edition, 1878, p. 557. ^ jn^^ pp 13^ 14, 



DECADE II. VOL. IX. NO. XI. 32 



