114 LIST OF CONTRIBUTORS. 



Lewis, Henry Carvill. On strontianite and associated minerals 

 in Mifflin Co. P '76. 11 



A garnet with inverted crystallization. P '80, 241 



■ A new polariseope. P '80, 241 



A new locality for siderite. P '80, 242 



Magnetite markings in muscovite. P '80, 242 



■ A new locality for asbolite. • P '80, 243 



Epidote in molybdenite. P '80, 243 



The optical characters of some micas. P '80, 244 



On an exfoliating talc. P '80, 252 



On the measurement of plane angles. P '80, 252 



Tin in North Carolina. P '80, 253 



On siderophyllite, a new mineral. P '80, 254 



On sterlingite and damourite. P '80, 256 



Vanadium in Philadelphia rocks. P '80, 256 



A new locality for epsomite. P '80, 257 



The surface geology of Philadelphia and vicinity. P '80, 258 



On the Bryn Mawr gravel. P '80, 277 



On dendrites. P '80, 278 



On some enclosures in mica. P '80, 278 



■ On a Jurassic sand. P '80, 279 



The minerals of Surry County. N. C. P '80, 280 



A new locality for lignite. P '80, 281 



On serpentine in Bucks County. P '80, 281 



The iron ores and lignite of the Montgomery Co. valley. 



P '80, 282 



An enclosure in quartz. P '80, 292 



— On a new fucoidal plant from the Trias. P '80, 293 



■ The Trenton gravel and its relation to the antiquity of 



man. P '80, 296 



Note on philadelphite, a new mineral. P '80, 310 



On philadelphite. P '80, 313 



— A Potsdam Sandstone outcrop on the S. Valley Hill of 

 Chester Valley. P '80, 329 



Pseudomorphs of serpentine after dolomite. P '82, 'M) 



New localities for barite. P '82, 38 



— On a new ore of antimony. P '82, 38 



On a fault in the Trias near Yardleyville. Pa. P '82, 40 



New localities for gypsum. P '82, 48 



A new locality for hyalite. P '82, 49 



Note on autunite. P '82, 49 



