CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
271 
The four following analyses represent andesites from the Copper 
River Basin. Analyses T, TT, by W. F. Hillebrand, record No. 2075. 
V,W, by George Steiger, record No. 2080. 
T. Dark, vesicular, porphyritic lava, late eruption, Mount Wran- 
gell. Torn dose. Contains labradorite, hypersthene, olivine, and mag- 
netite in a brown glassy base. Collected by W, C. Mendenhall. 
U. Gray, porphyritic, well-crystallized older lava, Mount Drum. 
Tonalose. Contains plagioclase, hornblende, biotite, hypersthene, 
magnetite, apatite, and zircon in a fine gray hypocrystalline base. 
Collected by W. C. Mendenhall. 
V. Augite-andesite, lower north slope of Mount Sanford. Kallerud- 
me. Contains plagioclase, augite, and magnetite in a macrocrystalline 
groundmass of the same minerals. Collected by F. C. Schrader. 
W. Hypersthene-andesite from near V. LaHsenose. Contains 
plagioclase, hornblende, hypersthene, and magnetite in a glassy 
groundmass of mainly plagioclase and hypersthene. Collected by 
F. C. Schrader. 
Analyses T to W are hitherto unpublished. 
Si0 2 .. 
A1A- 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 Oat 105°... 
H 2 above 105 
Ti0 2 
ZrO, 
NiO . 
MnO 
BaO. 
SrO . 
Li 2 G trace? 
T. 
• 
U. 
v. 
w. 
61. 31 
. 62.67 
70.94 
67. 04 
16.70 
16.62 
13. 96 
16.71 
1 . 30 
3.25 
1.74 
1.46 
4. OS 
1.17 
1.69 
2.08 
3.44 
3.08 
.12 
1.09 
6.10 
5. 56 
1.13 
3.26 
4. 05 
4.24 
5. 64 
5.07 
1.58 
1.67 
4. 03 
1.84 
.L>2 
.23 
. 09 
.08 
. ."»() 
1.01 
.45 
.51 
. 73 
.48 
. 30 
.51 
.01 
.01 
. 05 
.05 
.IS 
.15 
.10 
.27 
.02 
.01 
none 
none 
.14 
.11 
.15 
.16 
.05 
.06 
.06 
.03 
.02 
.03 
trace 
trace 
trace? 
trace 
100. 29 
100.35 
100. 45 
100. 16 
C0 2 and 8 absent. 
