MARYLAND GEOLOGICAL SURVEY 257

———— Notice of two New Fossil Mammals from Brunswick Canal,
Georgia; with observations on some of the fossil quadrupeds of the
United States.

Amer. Jour. Sci., vol. xliii, 1842, pp. 141-144, 2 plates.

Tooth of Mastodon longirostrls from the Miocene of Maryland, hitherto found only
in Europe, mentioned incidentally, p. 143.

LOOMIS, ELIAS. On the Dip and Variation of the Magnetic Needle
in the United States.

Amer. Jour. Sci., vol. xliii, 1842, pp. 93-116.

Differs from Courtenay in the value for the dip at Baltimore.

MARKOE, FRANCIS, JR. [Remarks and list of fossils from Miocene.]
2nd Bull. Proc. Nat, Inst, Prom. Sci., 1842, p. 132.

Enumerates several new forms found with Mr. Conrad, which were later described by
the latter.

ROGERS, HENRY D. An Inquiry into the Origin of the Appalach-
ian Coal Strata—Bituminous and Anthracitic.

Trans- Assoc. Amer. Geol. and Nat., 1842, pp. 433-474.

A comprehensive general paper in which the author considers both the bituminous
and anthracite formations to be continuous with each other, and that they extended
form Pennsylvania to Alabama and eastward to the Appalachian valley. Such an
extent is explicable only on assumption of the oceanic origin of coal

———— W. B. & H. D. On the Physical Structure of the Appa-
lachian Chain as Exemplifying the Laws which have Regulated the
Elevation of great Mountain Chains.

Eepts. Amer. Assoc. Geol. and Nat., 1842, pp. 474-531.

(Absts.) British Assoc. Repts., 1824, Pt. II, pp. 40-42; Proc. Assoc. Amer.
Geol. and Nat. 1840-42, pp. 70-71; Amer. Jour. Sci., vol. xliii, 1842, pp. 177-178;
vol. xliv, 1843, pp. 359-362.

Part I deals with a description of the area, its divisions; their structure, especially
inverted dip, length, persistence and parallelism of axes and the increasing interval
between them to the northwest.

Part II deals with a theory of the flexure and elevation of the strata, which are
due to a combined undulatory and tangential movement.

RUFFIN, ED. An Essay on Calcareous manures. 8vo. 316 pp.
Petersburg, Va., 1842. 3rd Edit.

General discussion of the tidewater marls, pp. 194-234. First use of marl in Mary-
land in Talbot County, 1805, by Mr. Singleton. (1st Edit. 1832, 2nd Edit. 1835.)

1843.

CONRAD, T. A. Description of a new Genus, and Twenty-nine new
Miocene and one Eocene Fossil Shells of the United States.
Proc. Acad. Nat. Sci., Phila., vol. i, 1843, pp. 305-311.
Eleven of the specimens were found in Maryland.