216 



TRANSACTIONS OF THE 



[ArR. 24 



often the case*, the scapolite is secoudaiy after feldspar. But 

 no section has j'-et been procured in which the process can be 

 traced. 



Lacroix| has described a rock occurring at Pierrepont, which 

 from its character and association is evidently the equivalent of 

 the rock under consideration, though differing from it in some 

 respects. He also mentions several other localities in the State 

 where the same rock occurs with crystalline limestone, the 

 association of the two seeming to be quite common. 



Somewhat similar rocks have been described by Becke| from 

 lower Austria ; and there a transition is seen between the 



Fig. 2. Scapolite rock. 



Pyroxene represented with light border. 



Titanite " " dark " 



Pyrrhotite shaded. 



Scapolite, with irregular change, enclosing all other minerals. 



Width of field, 2 min. 



* L''icroix, A., Sur la transformation des feldspaths en dipyre, Bull. Soc. 

 Mm. Fr., XIV.. p. 15. Judd. J. W., Mineralogical Majrazine, VIll., p. 180. 



t Lacroix. A., Thoses prusentdes a la Faculto des Sciences dc Taris, ire Con- 

 tributions a 1 Etude des Gneiss a Tyroxone ot des Roches a Wernorite, p. 183. 



t Boeke.F-, Die Gneiss formation des noiderOsterreiehischen. Waldviertel; 

 Teehermak s Mittheilungen, IV., p. 3C5, et seu. 



