IGNEOUS AND CRYSTALLINE ROCKS. 177 
F a. H I 
BIOS. sie se 3 seeemepitls Se sal senteind alee dance emiedutioeus semumaseeuacinat 61.58 | 54.20] 56.07 51. 54 
ANQO 8 ss piaisis seSizieciemtacs + san weenie Bee ae ceEE MSc cte sig Ga adimesmeaaine dg 15.89 }| 15.86] 19.06 20. 31 
Gg O Sacens se eqermitimcts¢ odongyaprate SSeS ba ates oiciaisiacdisjeaisia wise Seni OE Oe 2.19 3. 32 5.39 4. 64 
BOO nesses dsmece ear sed acing ae inivemicinat ce cnet he aweananaadeteieases 5. 50 4.14 «92 3. 56 
MBO, ices Si eters aie feet cecnsnasai ab Suara iene nye ba SSN E MIRA ME RREMERRESES 2.69 3. 51 2.12 3.16 
CaO 6. 49 5.32 7.70 9. 55 
NazO 3.04 3. 28 4. 52 4. 29 
Bes iid? oh 3. Ee 1,24 2. 47 
20 @ o- . . 
Hi0 above 110°....... eatd ") 126] 2/40 \ +99 \ 34 
WO Gsciesccenscaiscess aes ose cegeaeievastns = - 63 1.35 1.24 32 
woe SGREREG KER RAMA TE Oe e See ee a Dee ca E ze eisiecaie ind ae Sa ainjeeiawieteioincs 12 68 .16 57 
PO saceseias seeieearess Se eteeeei at Pacts aieine 3h se kicnedhelet tee aan suturisiecerereieell nana See Obs eeede HAS aie ee alaaen sacs 
INDO oo nr oct a eucner yeaa ae raseicink bic Hazgispmmins eclclnaeaetlese Saeed miad trace? (17 eee eee 
QOlasisnjessneaitdioegtedicinaies escionintiniteleseaetie gis essere ada tseratesaied - 20 19 +23 32 
EO cadet ah oid hainsiaedink Hae GAOT ates Ede eele BR aweNe Seam acre trace? 04. fas assee slic: cece 
BaO ocicciscienae te ter seme add cencaedaee tak eames ees eeeauuies seeeecemcwe - 06 BY lens ayiealleee seers 
Lin... trace’) $race-|issasevelsadee ce 
COs... MONE: | VADs os neac cl ccnecans 
POS soja sinsard Seinin igs eneeinsaerenis veae yg syese see ae RS RE ERE R ERE ETE Sere - 06 DG i acs c, ciel eevcorie cae 
100. 38 | 100.28 | 99.64} 101.07 
Rocks J to R. Collected by J. E. Spurr. Rocks J to P are described by him in 
Am. Geologist, vol. 25, p. 210. Analyses by H. N. Stokes, record Nos. 1809 and 1822. 
J. Alaskite, Chilkoot Pass. Liparose. Dike in granite. Contains quartz, ortho- 
clase, and some twinned feldspars, accessory zircon, actinolite, magnetite, and siderite. 
K. Alaskite porphyry, Fortymile Creek, near Canyon Creek. Lassenose. Dike. 
Contains quartz, orthoclase, and some plagioclase, with accessory biotite and epidote. 
L. Alaskite, Skwentna River, 12 miles above its mouth. Toscanose. Dike. Con- 
tains quartz, orthoclase, and microcline, with no dark minerals. 
M. Alaskite, Tordrillo Mountains. Alaskose. Dike. Consists of quartz, orthoclase, 
and microcline, with no dark minerals. P. R. C. 1275.- 
42 09 10 
1.86 1.00 17 
5.33 3. 52 3.19 
4. 56 4.89 4. 80 
16 ro a 15 
48 + 26 53 
10 +06 09 
60 -10 trace 
13 | trace trace 
99.86 | 99.66 99. 82 
In J to M there are traces of P20; but no COs. Manganese is also present in traces. 
N. Augite belugite, Skwentna River, near Hayes River. Hessose. Dike. Con- 
tains essential feldspar, intermediate between andesine and labradorite, augite, and 
some hornblende. Alsoa considerable amount of pyrite. P. R. (. 1274. 
O. Tordrillite, Tordrillo Mountains. Alaskose. Dike. Contains phenocrysts of 
quartz, orthoclase, anorthoclase, and anorthoclase-albite. Groundmass consists of 
quartz and orthoclase. No dark minerals except very small quantities of secondary 
hornblende. P. R. C. 1276. : 
P. Augite aleutite, near Kalinai Pass, Aleutian Peninsula. Andose. Lava. 
Chiefly labradorite, tending toward andesine, with a considerable amount of pale- 
green augite. P. R. C. 1277. 
