The characters of this genus are imperfectly known, none of the specimens being complete. Supposing however, that the association is a natural one, we have a genus with leaves and pedicellate fruits much more similar to those of _Thrincoma_ than to those of _Thrinax_, and at the same time a columnar, rimose and pithy trunk like that of _Thrinax_ and _Coccothrinax_. The seeds appear to differ from those of all related genera in the possession of large irregular convolutions. The coriaceous leaves, small fruits, subapical embryo, and other differences separate this genus from _Coccothrinax_. =Thringis laxa= sp. nov. The trunk is columnar or somewhat enlarged upward, about 3.6 m. high and 12 cm. in diameter. Surrounding its base was a dense turf of fine upright rootlets. The bark was rough and rimose. The leaves are similar to those of _T. latifrons_, but smaller, the segments being about 70 cm. long by 33 mm. wide. The size of leaves is thus about the same as those of _Thrincoma alta_, but the texture is thin and flexible, the veinules being slender and not prominent on either side. The pubescence is much thinner than that of _T. alta_ and of a silvery-gray color. A palm collected in December, 1899, at Vega Baja, but without fruit (no. 1041). The habit and trunk are not those of _Thrincoma_, but the form and texture of the leaves and ligule associate the species with _Thrincoma alta_ rather than with the palms here placed in _Thrinax_. The columnar habit and protected habitat are reflected in the small ligule, 18 mm. across, and the relatively broad petiole, 13 mm. wide. It appears from the dried specimens of this species and _T. latifrons_ that the leaves may have been “full,” or irregularly folded, instead of strictly and equally expanded as in _Thrincoma alta_, and the greater width of the segments is a further indication of this possibility. The rigidity of the leaf of _Thrincoma alta_ can be maintained because the segments are narrow and do not open widely. The soft texture of the leaves of this palm is recognized by the natives who use it for making hats and call it “yaray” the same name which is applied in this part of the island to _Inodes causiarum_. =Thringis latifrons= sp. nov. The leaves, inflorescence and young plants of a palm collected by Sintenis (no. 3278) on Monte Calabaza near Coamo are much larger and coarser than those of _Thrincoma alta_. The total length of the middle segments of the leaf would be over a meter, and the width of the larger divisions is over 5 cm. The thickness of the petiole at the base of the ligule is over 10 mm. The form of the ligule is much like that of _Thrincoma alta_, though scarcely as large in proportion to the size of the leaf.