WS 44. Profiles of rivers, by Henry Gannett. 1901. 100 pp., 11 pls.
WS 62. Hydrography of the Southern Appalachian Mountain region, Pt. I, by H. A. Pressey. 1902. 95 pp., 25 pls.
WS 63. Hydrography of the Southern Appalachian Mountain region, Pt. II, by H. A. Pressey. 1902. 96-190 pp., 26-44 pls.
WS 69. Water powers of the State of Maine, by H. A. Pressey. 1902. 124 pp., 14 pls.
Series O—Underground Waters.
WS 4. A reconnaissance in southeastern Washington, by I. C. Russell. 1897. 96 pp., 7 pls.
WS 6. Underground waters of southwestern Kansas, by Erasmus Haworth. 1897. 65 pp., 12 pls.
WS 7. Seepage waters of northern Utah, by Samuel Fortier. 1897. 50 pp., 3 pls.
WS 12. Underground waters of southeastern Nebraska, by N. H. Darton. 1898. 56 pp., 21 pls.
WS 21. Wells of northern Indiana, by Frank Leverett. 1899. 82 pp., 2 pls.