[NDEX. 



459 



Orthoclase-freo diabase (coarse grained). See < tabbro, Ortho- 



clase-free. 

 Ortboolase-gabbro. See Gabbro Orthoclase. 

 Ortboclase-froe gabbro. See Gabbro, Oi i 

 Osceola, Contact of Keweenaw Series and PotedamSandstone 



in, 236, 237. 

 Otter Head. Huronian of, 400. 

 Owen, D. D„ 5, 37, 403. 



— on Eastern Sandstone, 351. 



Keweenawan rocks, 112. 



St. Croix Sandstone, 411. 



, Publications of, 17. 



— . See Norwood. 



Owen, I!., on Pigeon Kiver dikes, 370, 371. 



Pebbles in augite-syenite, 112. 



— of Albany and Boston Conglomerate, 04, 180, 191. 



Calumet and Hoela Conglomerate, 105, 195, 106. 



National mine. 94, 190, 191. 



Peninsula Bay. Trap of. 401. 

 Penokee Hnronian, 391, 392. 

 Percival mine, 257. 

 Petit Marais, 264. 



, Temperance Riyer Group at, 323. 



Phoenix Mine Group, 175, 176, 178. 



Physical Geology of Lake Superior. See Whittlesey. 



Pic Island, Trap of, 401. 



Pic, The. 415. 



Pic River, Huronian of, 401. 



Pie Island. 331. 



Pigeon Bay, Auiiuikie Group on, 372-374 



, Dike-rock from, 372. 



, Gabbros of, 372. 



Pigeon Point, Animikio Gronp at, 360, 370. 

 Pigeon Kiver, 414. 



, Acid oluptives of, 372. 



Animikie Group on, 370-372. 



, Dikes on, 371. 



. Hocks of, 37*2. 



, Gabbros of, 371,372. 



Pike Lake, Gabbros of. 274. 

 Pike Eiver, Slates of, 401. 

 Pine Rapids, Sandstone of, 249. 

 Plagioclase of amygdaloids, 88. 



augite-syenite, 113. 



hornblende-gabbro, 57. 



olivine-diabase, 69. 



olivine-free diabase, 63. 



ortboclase-free gabbro, 39, 40. 



, Angles of, 39, 40, 439. See also Tabulation 



vations of various rocks. 

 Point Magnet, 334. 

 Pointe aux Mines. 347, 34'J, 41.".. 

 Pokegoma Palls, Animikie Gronp at 883 184 

 Poplar River, Rocks of head-waters of, 145, 272. 



, Temperance River Group on, 328. 



PorcupiDe Mountains, 65, 206-224. 



, Authorities on, 207. 



Basic Belt of, first, 214-218, 432, 135. 



, second, 219, 220. 



belts, continuation of. 224-226. 



at Carp River and Little Carp River, 215-217. 



, Diabase-porphyrite of, 82, 215, 440. 



.Dike of, 253. 



.Fault of, 219. 



, Felsites and quartz-porphyries of, 99, 102, 103, 105, 106, 



343,150,209-214. 



l'olrllpl .. t.'JOO. 



.Height of. 2119. 



:. on, 209. 



, ttelaphyr of, 214. 



ich shale bell In i 



.Ollvir 



.Olivin.- ti Uabast 



.Porphyry of, 150,200-212, 182,431 



, Central, 208, 209. 



. Distributi i 



— , Limits of, 212-211. 



II, 132. 



, Inner, 217, 218 



,11., 



.Stratigraphy 



, Townships 50 and 51, R. 42 u - of, 217. 



, Upper Divisi n, 153,209. 



Pork Bay, Temperance Kiver gum;. 

 Porphyrin., Diabase. SwB 

 Porphyries, .v., A.1,1 original rooks. 

 Porphyrj ate, Porphyry. 



Porphyry, Felsitio. See Felsites. 



Porphyry, Granil lo, of Albany and Boston Conglomerate, 118. 

 119,190,191. 



Baptism Biver, 12:1,2:2. 



Beaver Ba] 



Bete Grise Bay, 117. 



Duluth, 119.270, 271. 



Eaglo Mountain, 124. 27:;, 271 



Blver conglomerate, 118. 168. 



Maw ske .[naw-, aw -in. 1 u l:i 1 



Minnesota. T.58, R.7 N 



Mount Bohemia, 116, 184. 



near Split Rock Eiver, 121. 



Tischer's Cr.ek. 120. 



. See Augite*syenite. 



—.Quart?., near Baptism River, 111 



of Beaver Bay, 108-108 :i"7. 



Bead 1,1,, ,,,i , 111,34ft 



the Calumet Conglomi rat 



Cedar Island, 108, 300, 307. 



Eagle Kin. 1 I 



Grand Marais. 110.391. 



Great Palisad 



Little Carp Eiver, 106, 21". 



ipicoten Island 



Potato Kiv.-r, 106, 23L 



Porcupine mountains, 42. 51. 105,210. 211 



Bed Rock Kay. lie 



Standard's Rock, 195 



Torch Lake Railroad, 104.190. 



Tyler's Fork, 106, 



.v.. Felsites 



— , Quart/less. 91-95. 



ofAlbanj and] l.iueratc. 94, 190, 191. 



.Base 



of Bead Island 



Brunschweiler River. 95. 



.Characteristics of. 91, 92 



, Color mi 92. 



. Constituents of, 92, 90. 



, augite, 93. 



, feldspars, 92, 93. 



. 'i 



of Duluth, 95. 



,Flowage structure in, 93. 



