F. Biotite-augite-latite, 4 miles southwest of Clover Meadow. Called "trachyte-andesite-tuff" in former edition of this bulletin. Contains plagioclase, biotite, augite, magnetite, apatite, and glass. Analysis by W. F. Hillebrand, record No. 1597. P. R. C. 762.

G. Augite-latite, Dardanelle flow, near Clover Meadow. Called "trachyte-andesite" in former edition. Contains plagioclase, in part labradorite, augite, iron ore, some olivine, apatite, and brown glass. The potassium is probably in the glass, as no potash mineral was observed. Analysis by H. N. Stokes, record No. 1645. P. R. C. 785.

H. Augite-latite, Table Mountain. Called "basalt" in former edition. Contains labradorite, olivine, augite, and magnetite. Analysis by Hillebrand, record No. 1273. P. R. C. 724.

I. Augite-latite, Table Mountain, near Clover Meadow. Contains labradorite, angite, olivine, magnetite, apatite, and glass. Analysis by George Steiger, record No. 1697.

J. Amphibole-gabbro, Beaver Creek, Big Trees quadrangle. Contains labradorite and amphibole, with a little pyrite and pyrrhotite. Analysis by H. N. Stokes, record No. 1752.

K. Amphibole separated from J. Analysis by William Valentine, record No. 1733.

L. Olivine-gabbro, just east of south end of Phoenix reservoir. Contains plagioclase, a few grains of alkali feldspar, augite, rhombic pyroxene, amphibole, olivine, magnetite, and iron sulphide, with a little secondary chlorite and epidote. Analysis by H. N. Stokes, record No. 1750.

For description of J and K see Turner, Amer. Jour. Sci., 4th series, vol. 7. p. 294. The description of L is hitherto unpublished.

12. MARIPOSA COUNTY.

Rocks collected by H. W. Turner, and partly described in his papers in the 14th and 17th Annuals. Additional data supplied by Turner.

A. Soda-granulite or aplite, about 4 miles west of Mariposa. See 17th Ann., Part I, p. 721. Contains plagioclase (albite?) and micropegmatite, with less epidote, quartz, sphene, and apatite. Analyses by W. F. Hillebrand, record No. 1461. P. R. C. 748.

B. Micropegmatite, Agua Fria Creek. See 17th Ann., Part I, p. 691. Contains quartz, plagioclase, brown mica, epidote, and a little iron ore. Analysis by Hillebrand, No. 1461. P. R. C. 746.

C. Soda-granite-porphyry, Merced River, below the mouth of the north fork. Published in 17th Ann. Contains feldspar, largely albite, hornblende, muscovite, abundant epidote, apatite, and a little iron ore. Analysis by George Steiger, record No. 1573. P. R. C. 774.

D. Granite-porphyry, about one-fourth of a mile north of Lake Tenaya, Yosemite National Park. See 14th and 17th Annuals. Contains orthoclase, quartz, plagioclase, and biotite, with a little iron ore and sphene. Analysis by Hillebrand, record No. 1432. P. R. C. 726. E. Granite, west of Lake Tenaya, Yosemite National Park. See 14th and 17th Annuals. Contains quartz, orthoclase, plagioclase, and biotite, with some hornblende, iron ore, sphene, and apatite. Analysis by Hillebrand, No. 1432. P. R. C. 725.

F. Amphibole-biotite granite, Nevada Falls trail, Yosemite Valley. Contains alkali feldspar, plagioclase, quartz, amphibole, biotite, magnetite, and apatite.

G. Biotite-granite, base of El Capitan, Yosemite Valley. Contains alkali feldspar, plagioclase, quartz, biotite, titanite, apatite, and iron oxides.

H. Brown mica separated from G.

Analyses F, G, and H by William Valentine, record Nos. 1732, 1733. I. Amphibole separated from quartz-monzonite, Tioga road, southeast of Mount Hoffman. Sp. gr. 3.203, 2.15°.

J. Mica separated from the same rock as I. Sp. gr. 3.05, 21°.
Analyses I and J by W. F. Hillebrand, record No. 1774.

Samples G to J are described by Turner in Amer. Journ. Sci., 4th series, vol. 7, p. 294.

K. Quartz-mica-diorite, Chowchilla River. See 17th Ann., Part I, p. 691. Contains plagioclase, quartz, a little orthoclase (?), brown mica, hornblende, rather abundant apatite, a little iron ore; one zircon-like crystal was noted. Analysis by W. F. Hillebrand, record No. 1461. P. R. C. 745.

L. Quartz-mica-diorite, Yaqui Creek. For the Educational Series of Rocks. Contains plagioclase, quartz, biotite, hornblende, a little pyroxene, iron ore, and apatite. Analysis by George Steiger, record No. 1643. P. R. C. 135. P. R. C. 135. Described by Turner in Bull. 150, p. 339.

M. Diabase, dike 14 miles northeast of Hornitos. See 17th Ann., Part I, p. 694. Contains plagioclase, partly labradorite, augite, brown hornblende, and iron ore. Analysis by Hillebrand, No. 1461. P. R. C. 750.

N. Igneous rock, near Cathay Hill. See 17th Ann., Part I, p. 694. Contains two minerals unidentified; neither is olivine. Analysis by Hillebrand, No. 1461. P. R. C. 749.