The seeds of Tilma caryotaefolia are like those of Curima, but considerably larger, rounder, and much smoother. The foramina are peripheral, but are much smaller and more shallow, those of Curima being surrounded, as it were, by a prominent rim which adds somewhat to the apparent width of the seed. In both genera the nuts are unsymmetrical, the side which has the largest foramen being distinctly larger than the others and in Curima the irregularly pitted sculpture is coarser.
ACROCOMIA Martius, Hist. Nat. Palm. 2: 66
A genus of palms distributed through tropical America from Mexico to Cuba and Paraguay. All the species are of stocky, compact growth, with a dense crown of numerous leaves. The trunk and the leaf-stalks are usually armed with strong, sharp spines, sometimes several inches long.
Although totally different on close inspection this genus has in Puerto Rico a superficial resemblance to the royal palm, which often deceives travelers. The similarity lies mostly in the two facts that both the royal and corozo palms are more robust and stiffly erect than the cocoanut, and that the leaf-divisions instead of lying horizontal and in one plane are tilted at different angles to the midrib, thus giving the foliage seen in the mass a somewhat unkempt appearance in comparison with the cocoanut.
In distinguishing the corozo palm from the royal palm when seen at a distance so great that the spines of the one and the columnar green leaf-sheaths of the other can not be seen, recourse may be had to the following facts. The leaf crown of the corozo palm is much rounder, thicker and more compact than that of the royal palm, since it contains many more leaves, and these persist much longer. The royal palm can also be known by the unopened leaves which project straight upward like flag-poles or lightning-rods, while in Acrocomia the leaves open as they are pushed out and seldom offer a suggestion of the spire-like effect.
Acrocomia media sp. nov.
Trunk 20–30 cm. in diameter near the base, thickened above to 50 cm. or less; height commonly about 6–8 m. rarely exceeding 10 m. Surface of trunk with slight annular impressions. Internodes armed with slender black spines, the larger 10–15 cm. long, mostly confined to the lower half of the internodes. Fruit green, becoming yellowish, the husk firmly fibrous, inedible; about 35 mm. in diameter, nearly spherical in shape, with a distinct apical papilla. Kernel 25 mm. wide by 22 mm. long; width of the cavity 18 mm. The type specimen was collected near Ponce (photograph no. 255).
The Acrocomia of Puerto Rico seems to differ from A. aculeata (Jacquin) in its robust habit and somewhat bulging trunk, while it is less stout and less swollen than A. fusiformis (Swartz). The name Acrocomia lasiospatha, although used by Martius and Grisebach has no warrant for supplanting fusiformis of Swartz, which must be preferred for the Jamaica species with the thick, swollen trunk.
In Jamaica there seem to be at least two species of Acrocomia, the larger of which is called the “great macaw” palm, and is described as having a fusiform trunk as thick as a man’s body. What is presumably the same species occurs in Cuba as shown by a photograph from the vicinity of La Gloria on the north coast. The greatest diameter of the trunk is three or four times the thickness near the base. In Puerto Rico no trees approximating these proportions were observed, the greatest amount of swelling probably not reaching twice the diameter below. According to Maza Acrocomia lasiospatha grows wild in Cuba and is known under the name “coroja de Jamaica.” Swartz described his Cocos fusiformis on the supposition that it was distinct from the Cocos aculeatus of Jacquin, from Martinique, by reason of the fusiform trunk. The species was, nevertheless, reduced by Martius to his South American Acrocomia sclerocarpa, perhaps because the spathe is said to be spiny, a character probably subject to great variation.
Jacquin’s name Acrocomia aculeata (1763) must, it seems, be used for the West Indian palm placed by Martius under his A. sclerocarpa, which is to be maintained, if at all, as a South American species. Jacquin declares that the habit of his tree is similar to that of Cocos nucifera and Cocos amara (Syagrus), and his figure shows a tall straight trunk tapering slightly upward, with no tendency to bulge. The spines of the trunk are few and the midribs are aculeate on both sides. The drawing of the fruit is 37 mm. long by 41 mm. wide and has a broad conic papilla at apex. As indicated above, such a tree was not noticed in Puerto Rico where all the corozo palms are distinctly, though slightly, thicker some distance above the base, though apparently never equaling A. fusiformis in this respect.