Essig, F. B. & L. Litten (Institute for Systematic Botany, Department of Biology, SCA 110, University of South Florida, 4202 E. Fowler Ave., Tampa, FL 33620-5200, U.S.A.; essig@chuma1.cas.usf.edu). A systematic histological analysis of palm fruits VII. The Cyrtostachydinae (Arecaceae). Brittonia 56: 375– 379. 2004.—Fruit specimens representing five taxa of the genus Cyrtostachys were examined histologically in order to characterize the pericarp anatomy of the monogeneric subtribe Cyrtostachydinae (tribe Areceae, subfamily Arecoideae), as part of an ongoing survey of the family. The pericarp in this genus can be characterized by a combination of papillate epidermis, heavy layer of tanniniferous/ pigmented cells below the epidermis, a system of vascular bundles with thick fibrous sheaths with purely fibrous bundles frequently above and below, absence of brachysclereids, and a very thin sclerified locular epidermis. On the basis of pericarp structure alone, the genus might be most closely related to the Gronophyllum alliance of the subtribe Arecinae. This diverges somewhat from the hypothesis of relationship with the Areca group of the Arecinae resulting from two DNA-based phylogenetic studies, and even further from the hypothesis of relationship with Iguanura suggested by another DNA-based phylogenetic study.