GEORGIA.

Rocks collected by A. H. Brooks, who supplies the petrographic data. Hitherto unpublished. Analyses by H. N. Stokes, record No. 1727.

A. Meta-quartz-diorite, 2 miles southwest of Sweden, Gordon County. Contains plagioclase, near labradorite, green hornblende, sometimes diallage, much vitreous quartz, and accessory magnetite, ilmenite, and orthoclase. Also secondary epidote, zoisite, uralite, chlorite, garnet, calcite, and leucoxene.

B. Augite-microcline-granite, 1 mile east of Rowland, Bartow County. Contains microcline, some plagioclase, abundant pyroxene partly altered into chiefly uralite and chlorite, some biotite with frequent inclusions of rutile, much blue vitreous quartz, apatite, zircon, and magnetite.

C. Quartz-gabbro, 2 miles southeast of Walleska, Cherokee County. Closely related to B. Contains essentially plagioclase, near labradorites, and augite. Accessory magnetite, ilmenite, apatite, and zoisite. Orthoclase is sparingly present. Quartz occurs in vitreous masses.

KENTUCKY.

1. THE ELLIOTT COUNTY DIKE.

Described by Diller in Bull. 38. Also in Amer. Journ. Sci., 3d series, vol. 32, p. 125.

A peridotite, var. kimberlite, consisting largely of olivine, sometimes altered to serpentine. Pyrope, ilmenite, a few scales of biotite, a little enstatite, and a trace of apatite are present as primary minerals. Secondary minerals are serpentine, dolomite, magnetite, and octahedrite. P. R. C. 799.

A granitic rock occurs with the peridotite. It consists chiefly of feldspar, orthoclase, and plagioclase, with a considerable amount of quartz and ilmenite, and traces of hornblende, sphene, and apatite. Analyses by T. M. Chatard, record Nos. 272, 273, 282, 305, 351, 352, 353, 354, and 358.

The following analyses are of sedimentary rocks adjoining the dike: F. Calcareous standstone.

2. THE CRITTENDEN COUNTY DIKE.

A mica-peridotite, described by Diller in Amer. Journ. Sci., 3d series, vol. 44, p. 286. Contains biotite, serpentine, and perofskite, with less apatite, muscovite, magnetite, calcite, chlorite, and some other secondary products. P. R. C. 800.

A. The rock described by Diller. Analysis by W. F. Hillebrand, record No 1241.

B. An unpublished analysis of probably the same rock, from a shaft 40 feet deep at Marion. Collected by J. R. Procter, analyzed by L. G. Eakins, record number 965.

TENNESSEE.

Gabbro, 2 miles south of Limestone Cove, Unicoi County. Collected by Arthur Keith, who furnishes the petrographic data. Analysis by W. F. Hillebrand, record No. 1707. Contains hypersthene, plagioclase, and magnetite.

a Equivalent to 0.07 S. Assumed to be pyrite, no pyrrhotite being present.

MISSOURI.

Granite and porphyry, 6 miles east of Ironton. Described by Haworth in Mo. Geol. Survey, vol. 8, Annual Report, pp. 140, 180, and 213. Analyses by W. H. Melville, record No. 1206.

A, B. Granite. A, P. R. C. 1027; B, P. R. C. 1028.

C, D. Porphyry. C, P. R. C. 1029; D, P. R. C. 1030.

Rocks composed principally of orthoclase and quartz, with some microcline, plagioclase, and biotite, and minor accessory minerals.