PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 114(2):501-508. 2001. Further characterization of Caracara creightoni Brodkorb based on fossils from the Quaternary of Cuba (Aves: Falconidae) William Suarez and Storrs L. Olson (WS) Museo Nacional de Historia Natural; Obispo 61, Plaza de Armas, La Habana CH 10100, Cuba; (SLO) Department of Systematic Biology, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560-0116, U.S.A. Abstract. — Caracara creightoni, previously known from three fragmentary fos-sils from New Providence Island, Bahamas, is here documented from two Qua-ternary sites in Cuba. It appears to have been a smaller species than C. cheriway, but with a more robust biU and quadrate and other cranial differences, relatively shorter wings, and more robust hindlimb elements. The living species C. cheriway appears to be a relatively recent arrival in Cuba so that it is likely that fossils of Caracara from the West Indies may all belong to extinct endemic species. In his report on Quaternary birds from a sinkhole on New Providence Island, Baha-mas, Brodkorb (1959) erected a new spe-cies, Caracara creightoni, based only on a single fragment of carpometacarpus con-sisting mainly of the major metacarpal. Al-though Olson (1976) regarded this with skepticism, he was forced to concede that it came from a caracara and that it had a few apparently distinctive features. Never-theless, he adopted a very conservative ap-proach and considered all of the then-named fossil forms of Polyborus (now Ca-racara again — see Banks & Dove 1992) to be referable to Caracara plancus sensu lato. This conclusion was reversed follow-ing the discovery at the type locality of an incomplete quadrate and the distal end of a tibiotarsus that were distinct from C plan-cus, so that C creightoni was reinstated as a good species despite the paucity of ma-terial (Olson & Hilgartner 1982). An incomplete skull and two portions of femora from Quaternary sites in Cuba were referred to Caracara creightoni by Suarez & Arredondo (1997), although these were not described or illustrated. The identifica-tion of the femoral portions we now regard as uncertain because of the difficulty of identifying incomplete specimens, but we here describe the skull along with addition-al more recently collected postcranial ma-terial from Cuba in an attempt to further characterize the species C creightoni. Un-fortunately, although vertebrate fossils have been found in many localities in Cuba, very few have been accurately dated and all of those discussed herein can only be assumed to be Quaternary in age (Suarez 2000). Comparative material examined. — Com-plete skeletons unless otherwise noted: Ca-racara cheriway USNM 11679 (partial postcranial), 19664 (skull), 19670-71, 19682 (skull), 321805, 322338, 343845-46, 346402, 428041, 431612, 553229-30. Ca-racara plancus 18478, 227375 (skull), 345779-80, 488293 (skull), 490931, 614583-84. Caracara lutosus 19916. Systematics Class Aves Family Falconidae Genus Caracara Merrem, 1826 Caracara creightoni Brodkorb, 1959 Figs. 1-3 Referred material. — Skull consisting of most of the rostrum, the interorbital bridge.