William Henry Larrabee, Popular Science Monthly (1883)
“ Another remarkable adaptation of leaf-forms is exemplified in the Brazilian plant called the Bauhinia, the leaves of which are deeply cleft into two lobes, and given a form which is graphically described by the name Unha de boi, "ox-hoof," which the Portuguese give to the plant. At daybreak, the leaves are borne with both lobes spread out horizontally; as the sun rises in the sky, the lobes rise, and are drawn toward each other, till, in the more sensitive species (Bauhinia Braziliensis) , they are completely doubled up, with their backs in contact. ”
