- Langdon, Frank Warren, 1852-1933, author4
- Langley, S. P. (Samuel Pierpont), 1834-1906 author1
- Langley, S. P. (Samuel Pierpont), 1834-1906, author1
- Langworthy, C. F. (Charles Ford), 1864-1932, author1
- Lankester, E. Ray (Edwin Ray), Sir, 1847-1929, author1
- Lanphear, Emory, author5
- Lapsley, Frank L., author1
- Larkin, John H.1
- Latimer, Thomas S. (Thomas Sargent), 1839-1906 author1
- Latimer, Thomas S. (Thomas Sargent), 1839-1906, author1
- Lautenbach, Louis J., author6
- Law, Hartland.1
- Law, James, 1838-19211
- Lawson, Robert.1
- Le Hardy, J. C. (Julius Caesar), 1831-1
- LeConte, Joseph, 1823-1901, author1
- Leaman, H. (Henry), 1839- author1
- Leaming, James R. (James Rosebrugh), 1820-1892, author1
- Lederman, M. D. (Moses David), 1868-1952 author3
- Lee, Arthur Bolles, 1849-19271