512. Leconte, J. L. Notes on the Geology of the Survey for the Extension of the Union Pacific Railroad from the Smoky Hill River, Kansas, to the Rio Grande. Map, rare, 76 pp. Phila., 1868.$1.25
513. Leidy, Jos. (1.) Ancient Fauna of Nebraska. (2.) Memoir of Extinct Sloth Tribe of N. America. Two Monographs in 1 vol., 4to, maps and numerous fine plates. A perfect copy, boards, 1852-53.$1.75
514. Leidy, Jos. Contributions to the Extinct Vertebrate Fauna of the Western Territories. 4to, 358 pp., 37 full-page lithogrs. plates, paper, uncut. A great classic. Wash., 1873.$1.50
515. Leidy, Jos. Extinct Mammalian Fauna of Dakota and Nebraska. Includes also Synopsis of the Mammalian Remains of N. America. Illus. with 30 plates, a map and preceded by F. V. Hayden’s introduction on the Geology of the Tertiary of Dakota and Nebraska. Jour. Acad. Nat. Sciences. 4to, boards, uncut. Published at $12.00. Phila., 1869.$3.75
516. Leidy, Jos. Memoir on the Extinct Species of American Ox. Author’s separate. 4to, 20 pp., 5 plates, printed covers. Wash., 1852.85c.
517. Leidy, Jos. Memoir of the Extinct Sloth Tribe of N. America. 4to, paper, 16 plates. Wash., 1855.$1.00
518. Leidy, Jos. Portrait of Dr. Joseph Leidy. Superb Etching on heavy parchment paper, by James S. King. One of 150 numbered and signed artist’s proofs; bust, head three-quarters to right; size of etched surface, 14 × 17 inches. This portrait has been pronounced an excellent likeness by friends of the eminent scientist. Price, delivered, $15.00, reduced to$9.00
519. Lesley, J. P. Dictionary of the Fossils of Pennsylvania and Neighboring States. 3 vols., illus., by 3000 figures. 1889.$2.75
520. Lesquereux, L. (a) The Cretaceous Flora of the Western Territories. Wash., 1874. 4to, 30 plates (Hayden Mono., vol. 6). (b) Contributions to the Tertiary Flora. Wash., 1878. 4to, 65 plates. (c) Tertiary Fossil Plants, from Hayden’s Expl. Exp., 1870. H. S. T., 1872. 22 pp., paper covers, rare. (d) Fossil Plants of the Coal Measures of the U. S., with Descriptions of the New Species in the Cabinet of the Pottsville Sc. Asso., Pottsville, 1858. 24 pp., 2 plates, rare, paper. (e) Report on Fossil Flora. (Sup. to 5th An. Rep. U. S. Geol. Sur. Ter.). Wash., 1872. 22 pp., paper. As a lot.$3.50
520A. Lyell, Charles. Elements of Geology. Colored Profile, many illus., 12mo. First American edition. Phila., 1839.$1.00