62 ANALYSES OF ROCKS AND MINERALS, 1880-1908. 
2, SEPULCHRE MOUNTAIN. 
Rocks described by Iddings, 12th Ann., p. 633. Also in Bull. Philos. Soc. Wash- 
ington, vol. 11, p. 210, and in Mon. XXXII, pt. 2. 
A. Pyroxene andesite. Tonalose. Essentially composed of augite, hypersthene, 
and plagioclase. Analysis by J. E. Whitfield, record No. 923. 
B. Pyroxene andesite. Andose. Composition like A. Analysis by Whitfield, 
No. 923. 
(. Hornblende andesite. Andose. Essentially plagioclase and hornblende. 
Analysis by Whitfield, No. 922. 
D. Hornblende-pyroxene andesite. Tonalose. Contains augite, hypersthene, 
plagioclase, and hornblende. Analysis by T. M. Chatard, record No. 712. 
E. Hornblende-pyroxene andesite. Tonalose. Minerals as in D, with magnetite 
also. Analysis by Chatard, No. 712. 
F. Horblende-mica andesite. Yedlowstonose. Contains plagioclase, hornblende, 
biotite, and magnetite. Analysis by Whitfield, No. 924. 
G. Hornblende-mica andesite. Dacose. Contains plagioclase, hornblende, and 
biotite. Analysis by Chatard, No. 712. 
H. Dacite. Yellowstonose. Contains plagioclase, hornblende, biotite, and quartz. 
Analysis by Whitfield, No. 830. 
I. Dacite. Lassenose. Minerals as in H. Analysis by L. G. Eakins, record 
No. 1135. 
J. Andesite breccia. Lassenose. Not in paper cited. See Mon. XXXII, pt. 2. 
Analysis by Chatard, No. 712. Reported by Iddings as hornblende-mica andesite, 
containing hornblende, plagioclase, quartz, biotite, and a little magnetite. 
