MARYLAND GEOLOGICAL SURVEY 287

mately the same geological horizon. 2. That the Virginia deposits indicate a horizon
lower (older) in the geological scale than that of either of the formations Just men-
tioned. 3. That the Maryland deposits Indicate two well-marked horizons, of which
the upper one is the correspondent of the Virginian.

HITCHCOCK, C. H. The Crystalline Rocks of Virginia compared
with those of New England.

Trans. Amer. Inst. Min. Eng., vol. x, 1882, 477-480.

The correlation of the pre-Cambrian rocks of Virginia and Maryland with- those of
New Hampshire. The author regards the belt between Washington and Harper's Ferry
on the Potomac as Huronlan.

JONES, HOWARD GRANT. Notes on the Cumberland or Potomac
Coal Basin. (Read Sept. 11, 1880.)

Proc. Amer. Phil. Soc., vol. xix, 1882, pp. 11-110.

Section along Georges Creek from the Lower Barren Measures to the Pocono Sand-
stone.

LESLEY, J. P. (The Cumberland or Potomac Coal Basin.) Re-
marks on the paper by Mr. Jones.

Proc. Amer. Phil. Soc., Phila., vol. xix, 1882, p. 110.

SCHARF, J. T. History of Western Maryland, being a history of
Frederick, Montgomery, Carroll, Washington, Allegany, and Garrett
Counties from the earliest period to the present day. 2 vols. 4to,
Phila. 1882.

Topography and Geology by P. R. Uhler, pp. 13-46.

WHITE, I. C. Notes on the Geology of West Virginia. A Recti-
fication of the Section made by Mr. Howard Grant Jones, M.. S.
(Read June 17, 1881.)

Proc. Amer. Phil. Soc., vol. xix, 1882, pp. 438-446.

Gives a detailed columnar section along the north Potomac 1520 feet high, extending
from the Medina slates to the upper Coal Measures above Pittsburgh Coal.

1883.
ANON. Mining Notes.

Eng. and Min. Jour., vol. xxxvi, 1883, p. 315.

Chronicles the finding of three strata of marl-bearing shells and a large Jaw-bone
near Cambridge.

ASHBURNER, CHAS. A. Anthracite.

Mineral Resources U. S., 1882, Washington, 1883, pp. 58-60.
Statistics of shipments from 1873-1882 and price per ton.

BAILEY, J. TROWBRIDGE. The Copper Deposits of Adams County,
Pennsylvania.

Eng. and Min. Jour., vol. xxxv, 1883, pp. 88-89.

Origin and geological occurrences of the South Mountain ores in Adams county, Pa.,
and Washington county, Md.