CLARKE.] 
IGNEOUS AND CRYSTALLINE ROCKS. 
257 
D. Rhyolite, water's edge, head of Cleetwood Cove. Lassenose. 
Contains plagioclase, hypersthene, brown hornblende, and magnetite, 
in a feldspathic groundmass of trachytic t}^pe. P. R. C. 1315. 
E. Hypersthene-augite-andesita, large dike transsecting the north- 
western portion of the crater rim. Tonalose. Contains plagioclase, 
hypersthene, augite, and magnetite in a groundmass having a moderate 
amount of glass. P. R. C. 1313. 
F. Hypersthene-augite-andesite, west edge of Wizard Island. Ton- 
alose. Same minerals as E. P. R. C. 1309. 
Si0 2 
AlA 
Fe 2 3 
FeO 
MgO 
CaO 
Na 2 
K 2 
H 2 Oat 110°... 
H 2 above 110 
Ti0 2 
P 2 5 
Zr0 2 
NiO 
SrO 
BaO 
Li 2 
CI 
70. 
14. 
1. 
1. 
tr: 
99. 88 
B. 
77 
68. 17 
83 
15. 60 
35 
2.31 
25 
.94 
64 
1.02 
12 
2.76 
07 
5.15 
68 
2. 46 
07 
.09 
33 
.45 
38 
.54 
13 
.13 
05 
none 
me 
none 
02 
.03 
08 
.06 
ace 
trace 
11 
trace 
99. 71 
71.87 
14. 53 
1.28 
1.02 
.48 
1.59 
5.08 
2.84 
.06 
.22 
.41 
.10 
.04 
none 
.03 
.08 
trace 
trace 
99. 63 
I). 
70. 10 
15.18 
1.78 
1.09 
.74 
2. 27 
5. 15 
2.58 
.10 
.19 
.48 
.13 
.04 
none 
.03 
.08 
trace 
.03 
99. 9: 
60. 09 
17. 85 
2.03 
3. 45 
3. 50 
6.28 
4.17 
1.31 
.12 
.26 
.54 
.23 
none 
.05 
.05 
.05 
trace 
trace 
99.98 
59. 39 
18. 45 
1.79 
3.90 
3.13 
6.29 
4.29 
1.29 
.10 
.42 
.41 
.22 
none 
none 
.04 
.05 
trace 
trace 
99. 77 
Traces of manganese in all. Fluorine not sought for. No C0 2 , S, S0 3 , or Or 2 O s 
in any. 
Bull. 228—04 17 
