324 BIBLIOGRAPHY AND CARTOGRAPHY

JEWELL, F. H. Results of Stream Measurement.

14th Ann. Eept. U. S. Geol. Surv., 1S92-93, Washington, 1894, pp. 89-115.
The results of a study of the Potomac basin given ou pp. 134-140.

PARKER, R. W. Coal.

Mineral Resources U. S., 1893, Washington, 1894.

Statistics on area, production and value, pp. 188, 189, 194-200, 204, 307-311.

PEALE, A. C. Natural Mineral Waters of the United States.
14th Ann. Rept. U. S. Geol. Surv., 1892-93, Washington, 1894, pp. 53-88.
Incidentally discusses the mineral waters of Maryland.

———— Mineral Waters.

Mineral Resources U. S., 1893, Washington, 1894.
Statistics on o mineral springs for year 1893, pp. 774, 778, 789.

SHRIVER, HOWARD. Catalogue of Fossils Found at Cumberland,
Md. (n. d.) 4 pp.

SWANK, JAS. M. Progress of the Iron and Steel Industries of the
United States in 1892 and 1893.

Mineral Resources U. S., 1893, Washington, 1894.
Statistics on works (p. 15) and pig iron (p. 20).

WALCOTT, C. D. Notes on the Cambrian Rocks of Pennsylvania
from the Susquehanna to the Delaware.

Amer. Jour. Sci., 3rd ser., vol. xlvii, 1894, pp. 37-41.

WARD, LESTER F. Recent Discoveries of Cycadean Trunks in the
Potomac Formation of Maryland.

Bull. Torry Bot. Club., vol. xxi, 1894, pp. 291-299.
Records the new discoveries by Arthur Bibblns.

———— Fossil Cycadean Trunks of North America, with a Revision
of the Genus Cycadeoidea Buckland.

Proc. Biol. Soc., Washington, vol. ix, Washington, 1894, pp. 75-88.
Several references and a description of the Maryland forms.

WEEKS, JOSEPH D. The Potomac and Roaring Creek Coal fields in
West Virginia.

14th Ann. Rept. U. S. Geol. Surv. 1892-93, part ii, Washington, 1894, pp.
567-590.

Gives a brief description with columnar section of the Georges Creek field, p. 579.

WHITNEY, MILTON, and KEY, SOTHORON. Further Investigations
on the Soil of Maryland.

Md. Agri. Exper. Sta., Bull. No. 29, College Park, 1S94, 21 pp.