English systematic botanist and organizer, and botanical illustrator (1785-1865) who held the post of Regius Professor of Botany at Glasgow University, and was Director of the Royal Botanic Gardens, Kew. Rare 2.5 x 4 carte-de-visite portrait of William Jackson Hooker in a full-length pose, signed on the reverse in black ink, "W. J. Hooker, 1863." Published by the Maull & Polyblank photography studio of London. In fine condition, with collector's notations on reverse. A previous owner indicated that this photo derives from the collection of German botanist Eduard August von Regel, the director of the Russian Imperial Botanical Garden in St. Petersburg.