340 M. Ogilvie Gordon — Fauna of Uijper Capstan, South Tyrol 



Gidaris Saiismanni, Wissm. 



,, decorata, Mnst. 



,, Uraunii, Desor ... 



,, flexnosa, Mnst. ... 



,, Liagora, Mnst. ... 

 Entrochns [E)wrinus) Cassianus, Lbe., sp. 



,, ,, • gramdosus, Mnst., sp. ... 



,, ,, varians, Mnst., sp. 



,, (Pentact'inus) Tirolensis, Lbe., sp. 



,, ,, projnnqtiifs, Mnst., sp. ... 



CCELENTERATA. 



Clodophi/llia suMcevis, Mnst., s\). . ... 

 Isastnca Gitniheli, Lbe. ... 



Thamnastraa Zltteli, xon'^o'h.rva 



Toechastrtea OppcK, Volz. 



Stylina, n.sp., and several Thecosmilia, sp. ind. 



Keckoniiig the percentages from the Lamellibranchs as a sui'e 

 standard, the result yields 34 per cent, new species not yet known 

 in any of the Cassian or Eaibl zones of Alpine Trias ; 25 per cent, 

 species present in the Stuores- Cassian fauna but not in Eaibl 

 horizons ; 25 per cent, species common both to Stuores-Cassian 

 and to Eaibl faunas; and 16 per cent, species present in Eaibl 

 horizons but not in the Stuores-Cassian fauna. The thick-shelled 

 larger habitus of the bivalves at once marks a difference from the 

 Stuores-Cassian fauna, and presents a striking resemblance to the 

 character of recognized Eaibl faunas in this district, e.g. the Tra- 

 vernanzes Eaibl fauna at the higher horizons in Falzarego Valley 

 and the Schlern Plateau Eaibl fauna farther west. This faunistic 

 transition in the bivalves is undoubtedly attributable to renewed 

 local accumulations of tuff and volcanic dust, to strong current 

 • action, and the frequent reconstitution of littoral molluscan colonies 

 at one place or another as the eruptive invasions permitted. The 

 same transition seems to have taken place simultaneously in the 

 neighbouring localities of Eimbianco, Misurina. and Seeland Alpe 

 (Q.J.G.S., 1893, pp. 24, 33, 36). 



While the list shows clearly the close affinities of this fossiliferous 

 zone with the older Stuores-Cassian fauna, a few observations may 

 be made regarding the affinities with the younger Eaibl fauna. 



The most commonly occurring genera among the bivalves are 

 Avicula and Cassianella. According to .Dr. Bittner's terminology, 

 two species, A. Sturi and A. Cassiana, represent the older name of 

 A. Gea, while A. Cortinensis has close affinity with these species. 

 On the actual ground it was A. Sturi which distinguished itself by 

 the number of its representatives. On the other hand, Avicula 

 Tofance is a more distinctive local type. A. Sturi occurs in North 

 Tyrol at a high horizon of the Cardita strata, and continues in the 

 upper (Torer) Eaibl fossiliferous series. Hoernesia Johannis Austrim 

 and GervilUa angusta likewise continue, both in North and South 



