The royal palm of Florida is commonly referred to _Oreodoxa regia_, though with very doubtful propriety. Apparently on account of its great size, Cooper (Smithsonian Report 1860: 440. 1861) was inclined to identify it with _Oreodoxa oleracea_ which had also been reported from the Bahamas. The inflorescence and seeds collected by Curtis on the western borders of the everglades (no. 2676) are, however, obviously not those of _R. oleracea_ but are much more similar to those of _R. regia_. The branches of the inflorescence are much longer and more lax than those of the species of Cuba and Puerto Rico, from which they also differ in the frequent development of tertiary branches, in this respect resembling _Roystonea oleracea_. The fruits do not resemble those of _R. oleracea_ but are closely similar to those of the other species though somewhat smaller and more nearly spherical. Several reliable witnesses are on record to the effect that the trees are from 28 to 35 metres high and as much as 45 metres has been claimed, while among the royal palms of Cuba and Puerto Rico 18 metres is the commonly recognized limit of size. Mr. C. T. Simpson, of the U. S. National Museum, states that the palms of southwestern Florida lack the conspicuous bulge so characteristic in the trunks of the Puerto Ricon trees, and that they grow almost in reach of tide-water, while the natural habitat of the Puerto Rico species is evidently the limestone hills. In view of these differences it seems preferable to treat the Florida royal palm as a distinct species, for which the name =Roystonea Floridana= is proposed. Mr. Simpson also informs me that the royal palms seen on the islands off the coast of Honduras had the size and habit of those of Florida and not the relatively stunted appearance of those seen by him in Hayti and Jamaica. This fact is suggestive in connection with the popular idea that the palms of Florida are to be looked upon as recent arrivals from Cuba. Instead it seems more reasonable to believe that the royal palm of Puerto Rico, like the species of _Thrinax_ of that island, is a remnant of the flora of the time when the limestone hills were keys and hammocks like those of southern Florida, and relatively poor in vegetation able to crowd out the palms. =Acrista= gen. nov. Trunk slender, of uniform diameter. Pinnae horizontal, appendiculate. Inflorescences distinctly infrafoliar; spathes two, the outer short, the inner long and slender. Spadix once-branched, the branches coarse, tapering. Fruits with stigma lateral, seed deeply ruminate, embryo basal. Related to _Roystonea_, but differing in the more slender habit, the once-branched inflorescence, the basal embryo, and in having the leaflets in one plane. The color of the foliage is also considerably lighter than that of the royal palm so that from a distance the general appearance suggests the cocoanut rather than the royal palm.