452 



NEW YORK STATE MUSEUM 



Paleozoic topdgrapby, 419^-21^ 



Peneplains, 417^ 425^-27^ 



Perkins, cited, 375', 376\ 



Perovskite, 398^ 



Plilogopite, 295^ 296". 



Placoparia (Calymmene) multicosta, 

 367^ 



Plagioclase, 329^ 336*. 



Pleonaste, 329«. 



Porphyry, 355' ; syenite, 348'. 



Postglacial history, 293'-94^ 



Potsdam formation, 279''-81\ 354=- 

 '60^ 387^-88' ; thickness, 358^ 



Precambric disturbances, later, 278\ 



Precambric erosion, 276^-77*. 



Precambric faulting, 403'-5'. 



Precambric history, 273^-79'. 



Precambric igneous activity, 278''- 

 79^ 



Precambric igneous rocks, late, 345'- 

 54=. 



Precambric rocks, 294^-354= ; folia- 

 tion, 399»-402=; joints, 404^ 



Prepotsdam topography, 418=-19*. 



Prosser, cited, 363^ 372\ 372^ 373^ 

 377S 377^ 378«, 379*, 384^ 392=, 



4ir. 



Pyrite, 295^ 304^ 309^ 313«, 319=, 

 329". 



Pyroxenes, 295^ 295'^ 296S 300^ 

 301S 305S 309', 311*, 314^ 315^ 

 323=, 328^ 330^ 337^ 349=, 398=. 



Pyrrho.tite, 304^ 309^ 329". 



Quartz, 295=, 297S 300=, 304", 309^ 

 309^ 309^ 311", 313=, 313", 313^ 

 314=, 319*, 321*, 323=, 326^ 328^ 

 334*, 3^5^ 337=, 338\ 338", 348", 

 352=, 352", 352\ 355=, 356\ 356^ 

 395", 395^ 



Quartz augite syenite, 340^ ; analy- 

 ses, 333=, 339^ 353=. 



Quartz norite, analyses, 334'. 



Quartz syenite porphyry, analyses, 

 353=. 



Raquette river, 439\ 443\ 444". 

 Rhynchonella plena, 367*. 

 Ridges, northern, 434=. 

 Ries, Heinrich, cited, 448". 



Rock structures, 399=-416". 



Rome river, 442=. 



Ruedemann, Rudolf, cited, 393^ 



Sacandaga river, 439=, 441". 



St Lawrence valley, 438*. 



St Regis river, 439S 443\ 



Saranac formation, 299"-303^ 



Saranac river, 439", 440*, 442*;- 443". 



Scapolite, 295=, 304^ 329", 352=. 



Schists, 273S 295'. 



Schroon river, 439=. 



Scolitus minutus, 361^ 



Seeley, cited, 361=, 365*, 374S 376*, 



383*. 

 Serpentine rocks, 295". 

 Sillimanite, 295^ 296^ 

 Smyth, C. H. jr, cited, 302", 315*, 



316^ 317=, 329^ 330", 346*, 388^ 



397^ 398^ 447''; acknowledgments 



to, 271". 

 Solenopora compacta, 367^ 

 Sphaerexochus parvus, 366". 

 Spinel, 329". 

 Stenopora, 367=. 

 Streams, 437"-45=. 

 Strophomena sp., 366'. 



incrassata, 367=. 

 Syenite porphyries, 348^ 354\ 355' ; 



analyses, 351^ 353=. 

 Syenites, 275^ 312=-22=, 338», 340*, 



346'; analyses, 333\ 336=, 339"; 



amount of differentiation of, 325'- , 



26*; granitic phase of, 323"-25'; 



mineral composition, 313*-14* ; 



other areas, 316''-18' ; relation to 



anorthosite, 318''-22= ; variability 



of, 314*-16^ 



Titanite, 309^ 311", 313", 313^ 319*, 



329", 348', 356'. 

 Titanium, 353". 

 Topography, 416'-48' ; at close of 



erosion interval, 277*; paleozoic, 



419^-21'; Prepotsdam, 418=-19^ 

 Tornebohm, cited, 330'. 

 Trachytes, 395=-96\ 

 Tracy brook fault, 431^ 

 Trenton formation, 283^-84", 373*-82', 



393=; thickness, 376*. 



