The dried specimens which Willdenow studied were supplemented by notes of field observation by a court gardener, who was evidently also a botanist of some experience, to whom Willdenow refers as his “friend.” The living colors are described with considerable detail throughout the entire paper, which renders noteworthy the fact that the spathes are stated to be cinereous. This is in agreement with species of _Euterpe_ which have membranous spathes, but indicates a wide difference from the West Indian trees where the spathes are thick and fleshy and remain vivid green until they open and fall away. The name _Roystonea_ has been given to this ornament of the Puerto Rico landscape as a respectful compliment to General Roy Stone, the American engineer officer who secured the admiration of the people of Puerto Rico by his fearlessness and conspicuous energy in the Adjuntas road-building campaign which flanked the line of Spanish defenses, and whose subsequent interest in the improvement of the island will undoubtedly affect its future history. =Roystonea Borinquena= sp. nov. Plate _45. f. 2_. Trunk normally fusiform, 30–60 cm. thick, 12–18 m. high. Leaf segments 4–4.4 cm. in width. Inflorescence robust, compact, twice branched, the branches numerous and coarse, ferruginous, pubescent. Fruits long-oval, yellowish brown at maturity. Seeds 8 mm. by 6.3 mm., flattened about the hilum, rounded below; wall of endocarp smooth, adherent over a small area. The royal palm of Puerto Rico differs from that of Cuba in having the trunk generally shorter, more robust and more distinctly fusiform. The inflorescence is twice branched, with the branches more densely clustered, coarser and darker colored than those of the Cuban royal palm, _Roystonea regia_. They are also covered with a slightly hispid brown pubescence while Cuban specimens are much smoother and more pallid. The difference of habit, to judge from photographs of the Cuban species, is most apparent when the trees have grown in the open, as when planted in avenues or along roadsides. In Puerto Rico, trees which are obliged to compete with other vegetation are often tall, slender and unsymmetrical. The typical form is shown in our photograph (no. 250) taken in the plaza of Juana Diaz. Martius gives the width of the pinnae of the Cuban royal palm as from 8 to 12 lines. Cuban specimens show as much as one inch and a quarter, while others from Porto Rico are half an inch wider (44 mm.) of somewhat coarser texture and with more widely separated secondary veins. The fruits of the Puerto Rico palm are a deep yellowish brown when ripe, while those of the Cuban are said to become violet or bluish black. According to Martius, the fruits of the Cuban species are 6 lines by 4, but dried specimens show no such discrepancy of proportions and measure only about 8.5 mm. by 7.5 mm.