By Williams, Louis Otho, 1908- . Genre nc----- / Botany / Central America / Tropical plants / Central America . Names leaves / type / corolla / flowers / mexico and 945 more

By Williams, Louis Otho, 1908- . Genre n-mx--- / nc----- / Hoffmannia / Botany / Mexico and 2 more . Names corolla / hoffmannia / type / calyx / molina and 250 more

By Williams, Louis Otho, 1908- . Genre nc----- / Botany / Central America . Names plants / american / flowers / corolla / leaves and 597 more

By Williams, Louis Otho, 1908- . Genre nc----- / Botany / Central America . Names leaves / mexico / american / america / flowers and 971 more

By Williams, Louis Otho, 1908- . Genre nc----- / Botany / Central America / Tropical plants / Central America . Names leaves / corolla / american / flowers / mexico and 690 more

By Williams, Louis Otho, 1908- . Genre nc----- / Botany / Central America / Tropical plants / Central America . Names leaves / flowers / american / type / plants and 797 more

By Standley, Paul Carpenter, 1884-1963 . Genre s------ / nc----- / Rubiaceae / South America / Rubiaceae and 1 more . Names herb / mus / type / lata / peru and 4858 more