CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
137 
4. CRAZY MOUNTAINS. 
The greater number of the rocks in this group were received from 
J. E. Wolff, who has supplied the petrographic data. The few excep- 
tions are properly indicated. The three tinguaites and the elseolite- 
sycnite were described by Wolff and Tarr in Bull. Mus. Compar. 
Zoology, vol. 16, No. 12, 1893, in a paper upon " Acmite-Trachyte 
from the Crazy Mountains." The renaming of these rocks is due to 
Wolff. The analyses, except when otherwise stated, are by W. F. 
Hillebrand, record No. 1438. 
A. Granitite, Big Timber Creek. Toscanosc. Small dikes in main 
diorite stock. Contains quartz, orthoclase, plagioclase (oligoclase), 
and biotite. 
B. Hornblende-granitite, main stock, Big Timber Creek. Dacose. 
Contains biotite, hornblende, quartz, orthoclase, and plagioclase 
(oligoclase). 
C. Granite-porphyry, intrusive sheet, north part of the mountains. 
Lassenose. Contains orthoclase, albite, quartz, biotite, and green 
hornblende in a groundmass of quartz and untwinned feldspar. 
D. Porphyrite, intrusive sheet, Sweet Grass Creek. Lassenose. 
Contains hornblende and andesine in a groundmass of plagioclase, 
orthoclase, and quartz, with accessory magnetite. 
E. Porphyrite, dike in contact zone, Sweet Grass Creek. Toscanose. 
Contains brown hornblende, biotite, and labradorite in a groundmass 
of plagioclase, biotite, and hornblende, with a little quartz and 
orthoclase. 
F. Porphyrite, intrusive sheet, middle peak of Three Peaks. Aker- 
ose. Contains andesine, hornblende, augite, and biotite in a ground- 
mass of plagioclase, orthoclase, and quartz. 
Si0 2 
A1 2 3 
FeA 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 OatllO°.... 
H 2 above 110° 
Ti0 2 
PA 
MnO 
SrO 
BaO 
Li 2 
A. 
74. 37 
13.12 
.73 
.87 
.35 
1.26 
2.57 
6.09 
.05 
.25 
.29 
.06 
trace 
trace 
.10 
trace 
100.11 
B. 
64.47 
15.45 
2.25 
2.25 
2.68 
3.63 
4.54 
3.19 
.05 
.63 
.75 
.22 
.06 
.04 
.23 
trace? 
100. 44 
69. 93 
14.95 
1.78 
.55 
.60 
1.46 
5.30 
3.99 
.12 
.32 
.33 
.33 
trace 
.06 
.29 
trace 
100. 01 
i>. 
66.28 
16.21 
.80 
2.06 
1.57 
3. 53 
4.36 
3.20 
.12 
.78 
.50 
.20 
trace 
.05 
.34 
trace? 
100.00 
64.49 
17. 25 
.86 
2.42 
1.24 
3.79 
4.19 
4.15 
.06 
.54 
.51 
.23 
trace 
.08 
.30 
trace 
100. 11 
61. 08 
16. 62 
2.87 
2.56 
1.65 
3.66 
4.75 
3.90 
.44 
.97 
.73 
.63 
trace 
.08 
.32 
trace 
100. 26 
