Among the material brought together in the West Indies by Dr P. Wagenaar Hummelinck there are some coral colonies of the genus Tubastraea that are interesting from various points of view, in the first place because this genus of Madreporaria has but recently become known to occur in the West Indies. Vaughan & Wells (1943, p. 239) note as range of distribution of the genus Panamá, Indo-Pacific, Gulf of Guinea, and the West Indies. As I did not succeed in finding data in the previous literature on the occurrence of Tubastraea in the West Indian area, I wrote to Dr J. W. Wells, Cornell University, Ithaca, New York, who kindly informed me that the statement given above was based on otherwise unpublished recent finds of material from off Puerto Rico, whilst later a specimen was received from Curaçao. Moreover, the genus is mentioned in the Taxonomic Key to Genera of Living Western Atlantic Corals in Smith (1948, p. 108). Vaughan & Wells (l. c., pp. 238/239) define the genus Tubastraea with the following characters: “Like Endopsammia, but producing small subplocoid clumps by extratentacular budding from the edge-zone, polyps remaining organically united and with corallites united by some coenenchyme and feeble costae. Columella feeble, but occasionally well developed.” As the authors refer to the genus Endopsammia, the characters of the latter genus also may be cited here (l. c., p. 238): “Simple, subcylindrical, nonepithecate, fixed by broad base. Wall thin, costate. Septa thin, arranged according to Pourtalès plan only in early stages, later appearing normal. Columella small and spongy or scarcely developed.”