IV CONTENTS. 
Analyses of igneous and crystalline rocks—Continued. 
Lake Superior region—Continued. Page. 
5. Penokee-Gogebic region. ........-----+2-+-2 2222222 eee eee eee 50 
6. Pigeon Point, Minnesota... ....-.--------- +--+ 2-2-2 eee errr eee 61 
7. Mesabi district, Minnesota. ........-.------ +--+ -+-e++eee esters 54 
8. Miscellaneous rocks from Minnesota. .....-----------+----+------- 55 
South Dakota ..cc.-.csece eye es 24 Yedeeeeielece ae eee ve eee eee ees 57 
Wyoming. .... 222-2202 eee eee eee ett 57 
Yellowstone National Park and the Absaroka Range......-.-.----------- 60 
Ne Wlectrit: Peak nc cc: 2430, 0.0ceQniuesceeceaee ee ted 2s 42 Bees Y 60 
2. Sepulchre Mountain... ....-.- 2.2.2.2 2-22 e eee eee eee eee eee 62 
3. Absaroka Range. c.c2scscerneneenducaiie faeries eeu dao eeeeeS 63 
Crandall Basin: wc)... 2 tisescascaesaaee nee e ance eoeermseiee ees 63 
Sunlight intrusives. ..........-----+2- 2-2-2 eee eee eee eee 65 
Isha wooa Intrusives: cc: scesveieeseesleeeise eases etree mado ts 65 
. Dikesanbretcla.: -vseecexcueiseceee oh. 2 ec vins : aaeioeeme tess 66 
4, Absarokite-shoshonite-banakite series...........-..-------------- 67 
5, Miscellanéous rocks: ..2j.2.ccccdage. ce ceh feeee sega eeeeegedsae yrs ss 70 
Montana«ssccauoe 223554 eamngnb ease banerees bose bees tesa ress 74 
1. Madison and Gallatin valleys...........-...-.--.2-2--------+-+-+- 74 
o Butte district... ncexaese eanteeaasa piece sd eae hniemeweee dees 77 
3. Boulder batholith.......0..0..ccceu see 005s ecees cenwmeenies phos 79 
4, Crazy Mountains y aio. sched osu noelea ds sca cle ra oreaenaoneac ees 80 
5. Little Belt: Mountains. .22 2222225 oss eeu. se psi tar secoeeee sees 83 
6. Castle Mountain district.....2cc22e0 22 c2sse ss evseeeunb veces eee. 86 
7. Highwood Mountains. .0...2.¢.225es:2.:2¢¢edeeseebeee ese eseds 87 
8. Little Rocky Mountains............--..-222--20220 220-022 ee eee 90 
9.. Bearpaw Mountaing:.. 0.222.200 5 eS 524.02 pea nuekiaeeawecee ve ok 90 
10. Elkhorn mining district 2... .:. 2. 222 2 22s eae bessiveesi bd bee oes 92 
IL. Bitterroot. Range. -cc uence nonce a2. da cd Shee eenaeedeense ts 93 
12. Matyevill @-distrittsccccccceucuees ees ieee teanbtecsaneeite tees 93 
13... Livingston. quadrangle. j-....22:.02% 2 2242285 se ecwe ces Sea ees 94 
14. Philipsburg quadrangle.....................---. gSbisleeidiDbe betans 2 2 95 
[dah Owiens se aine sme de sattins sitdnnisesmaiaieselese ga we eeneeeegeek vues soea nee 95 
ColoradOs ccs ssc os4ciguiewerseeseae sey teesees zs exeeenseeeee Yee ses cesar 98 
1: Denver Basinisecssiuccssveaxd x2 exec ceces beede ee ost nak suse 98 
2. Pikes Peak district: ci.csiscccec5 see bsets of ceeoose ease beg ee bes see 99 
GIANIte 4552) ep siete Bs eee a Buen gu sells eos ace ae pate 99 
Rocks of Cripple Creek district.............--.2---2-2----22---++- 100 
Miscellaneous rocks. ......-...-...---22--2--- 2220-2 e eee eee eee 103 
3. Silver Cliffiand: Rositas.c.2 cucassoovecteencaetconta geese aeeeeeawe 104 
4. Buffalo Peaks sci dec iecstepets ¥ occre ar essvcteienctorertenee, ee rerene aichebnee 108 
5; Léadvillé Tépion ccc shcceaiot eg eases RE a ealuie eS 108 
6; Nenmile disttich. es visas: cee ee oedeenes nesses sc eee Saka 109 
73D Moun tAIns 442 2c neasey ed 23 x e4 seeneoenee eee eves Ceewseede 11 
8: West Wik Mountains scene. seccd acces teenie eesceyeteeedaceene LL 
9. a, Plata; Moumtaina: s).22)5 ¢2i2 2508 neaeenewalade 2 csac.t pa QGaae 112 
10. Silverton quadrangle. .......-......-2..2-22--22202 250-2 eee eee 113 
1. Ouray quadrangle .i.scie.c.eeaeretaciantanyue saree eeendaees 114 
12) Helluride:quadrangle sj ses secre de eaaeeen see ce en eaten’ 115 
13. Miscellaneous tocke:...2. «324204 saucaehec ps sey reeesss Guueeaseras 115 
Ueno Sata spat cas acetates Sa ties aa ON eee eat Sead erste 118 
Le Tinitie’ Qistrietisc easiness ones facathophaniot nd Saseintd meeuesoeselelnn 118 
2. Henry Mountains’..i092 2 222: 2.cehevedeeaae sd tides le oes castes 19 
