CLARKE.] 
IGNEOUS AND CEYSTALLINE ROCKS. 
113 
4. DIKES IN BRECCIA. 
Descriptions, hitherto unpublished, supplied by Arnold Hague and 
T. A. Jaggar, jr. Analyses A, B, D, by H. N. Stokes, record No. 
1804; C, E, F, G, H, by W. F. Hillebrand, Nos. 1765 and 1801. 
A. Hornblende-pyroxene-andesite, Eagle Creek. Camptonose. Con- 
tains plagioclase, hornblende, pyroxene, quartz, and apatite. 
B. Leucite-absarokite, Sunlight Valley. Lamarose. Contains phe- 
nocrysts of olivine and augite, with secondary alteration of the olivine 
to serpentine. The groundmass contains magnetite, augite, plagio- 
clase, and orthoclase. Leucite abundant. 
C. Grabbro-porphyry, Deer Creek. Shoshonose. Contains plagio- 
clase, pyroxene, olivine, ilmenite, and apatite. 
D. Hornblende-augite-andesite, Wind River Plateau. Tonalose. 
Contains phenocrysts of augite, hypersthene, and hornblende, plagio- 
clase, and line magnetite grains. 
A. 
B. 
c. 
D. 
Si0 2 
50.72 
16.01 
4.35 
4.20 
7.06 
9.02 
2.92 
1.13 
.40 
2.14 
1.08 
.29 
47. 32 
11.22 
2.91 
5.81 
15. 96 
7.11 
1.88 
3.79 
.31 
1.71 
.75 
.61 
50.29 
15. 85 
8.22 
1.43 
4.65 
7.71 
2.98 
3.-53 
1.77 
1.98 
.96 
.51 
60.15 
A1 2 3 
17.85 
Fe 2 3 
2.00 
FeO 
2.02 
MgO 
3.26 
CaO 
5.48 
Na 2 
3.95 
K 2 
2.36 
H 2 at 110° 
.25 
H 2 above 110° 
1.24 
Ti0 2 
.47 
P 2 5 
.22 
Zr0 2 
Cr 2 3 
none 
trace 
none 
V 2 3 
NiO 
none 
.07 
.09 
.11 
trace 
.85 
trace 
.11 
.05 
.22 
trace 
.13 
trace 
.15 
.09 
.15 
trace 
none 
trace 
none 
MnO 
.07 
SrO 
.10 
BaO 
.20 
Li 2 
none 
C0 2 
none 
CI 
" 
FeS 2 
100. 44 
99.89 
100. 27 
99.62 
Bull. 228—04- 
