MARYLAND GEOLOGICAL SURVEY 285

RUSSELL, I. C. On the former extent of the Triassic Formation of
the Atlantic States.

Amer. Nat., vol. xiv, 1880, pp. 703-712.

The author concludes " that the Triassic rocks in the Atlantic states were formed
in one estuary, in the northern end of which sandstone and shales were deposited, being
subjected to a greater subsidence than the southern extremity, where the shores were
low and favorable for the accumulation of carbonaceous mud and peat " (p. 711).

STEVENSON, J. J. Surface Geology of Southwest Pennsylvania and
adjacent portions of West Virginia and Maryland. (Read Apr. 1879.)

Proc. Amer. Phil. Soc., vol. xviii, 1879, pp. 289-316.

A study of the terraces in Garrett and Allegany counties. The present physiography
is considered due to the erosion which accompanied the submergence and emergence of
Glacial time.

WYSONG, THOMAS TURNER. The Rocks of Deer Creek, Harford
County, Maryland; Their Legends and History. Baltimore, 1880.
Printed by A. J. Conlon.

The author devotes one page (86) to the chrome pits and two to the slate series
(87-88). A popularly written account.

1881.

BROWN, T. Report of T. Brown, Inspector of Mines for Allegany
and Garrett counties.

Md. House and Senate Doc., 1881, F.

FRAZER, P., JR. Some Copper Deposits of Carroll County, Mary-
land.

Trans. Amer. Inst. Min. Eng., vol. ix, 1881, pp. 33-40.

Maps and sections are given, also several analyses and an estimate of the amount
of ore available. The deposits are situated near New Windsor. The workings are now
abandoned and the shaft filled up.

HEILPRIN, ANGELO. On the Stratigraphical Evidence Afforded by
the Tertiary Fossils of the Peninsula of Maryland.

Proc. Acad. Nat. Sci., Phila., vol. xxxii, 1880, pp. 20-33.

Holds that the Medial Tertiary is not synchronous with the South Carolina deposits
(Conrad), and that deposits intermediate between the Eocene of Fort Washington and
the Pliocene of the southeast extremity of the peninsula belong to two different periods
of formation; the later belonging to the Miocene, the older to the Oligocene.

JOHNSON, GEORGE. History of Cecil County, Maryland. 8vo.
548 pp. I-XII. map. Elkton, 1881.

Contains data indicating the gradual recognition and utilization of the natural
resources of the area.

LEIDY, JOSEPH. Description of Vertebrate remains chiefly from
the Phosphate beds of South Carolina.

Jour. Acad. Nat. Sci., Phila., 2nd ser., vol. viii, 1881, pp. 209-261.

Gives Myllobates gigas, M. pachyodon and Aetobatis arcuatus from Charles county,
Md., pp. 241-243, 245.