locality is also in doubt. Mr. Heller believes, however, that the
inflorescence came from a small _Thrinax_-like palm growing in the
limestone hills a few miles to the east of San Juan.
Family ARECACEAE
A large family, with abundant genera in the tropics of America and Asia,
but absent from tropical Africa. The Puerto Rico representatives may be
recognized very easily by the fact that the leaf crown is supported upon
a column of the sheathing bases, a character of which the royal palm
furnishes a conspicuous and ever-present example. Of the remaining
genera, one, the betel palm of the East Indies is sparingly introduced
about towns in the western part of the island and may be recognized at a
glance by reason of the extremely dark green of its foliage. The other
two genera are native palms confined to uncultivated areas and thus
seldom seen at close range from traveled roads. The mountain palm,
_Acrista_, covers the summits of many of the mountains of the island,
but _Aeria_ seems to be confined to the range of high limestone crags
which skirt the northern coast of the island between Bayamon and
Arecibo.
Key to the Genera of Arecaceae
Trunk tall and slender, tapering from a swollen base; spathes numerous
(7); inflorescence appearing in the axis of the rather persistent
lower leaves, long and slender; staminate flowers arranged in
rows.
AERIA.
Trunk robust or of uniform diameter; spathes 1 or 2; inflorescence
short and brush-like, not exposed until the enclosing leaf below
it falls away; flowers not set in rows.
Spathe single, the fruits 2.5 cm. long; leaf-divisions upright,
very dark green.
ARECA.
Spathes 2, fruits less than 1.25 cm. long; leaf-divisions
horizontal or oblique.
Trunk robust, thickened near the middle; leaf-divisions
inserted by twos and standing at different angles;
inflorescence twice or thrice branched, standing close
to the leaf-bases.
ROYSTONEA.
Trunk slender, of uniform diameter; leaf-divisions at
equal distances, horizontal; inflorescence
once-branched, at maturity 15 cm. or more below the
leaf-bases.
ACRISTA.
=Aeria= gen. nov.
A tall slender palm evidently related to _Gaussia_, but the embryo
lateral instead of basal, and the pinnae without basal cushions.
Among palms in Puerto Rico _Aeria_ resembles only _Acrista_, from which
it is readily distinguishable by the very slender habit, the swollen
base of the trunk, the much-branched slender interfoliar inflorescence,
the shorter sheathing bases of the leaves, and the numerous spathes.
The embryo of _Aeria_ is located near the longitudinal middle of the
seed on the side opposite the rudiment of the style, which is here
located at the base of the fruit instead of on the side as in _Acrista_.
The albumen is also uniform, except for a small central cavity and the
outer covering is fleshy rather than fibrous.
The position of the embryo is, perhaps, the most obvious difference
between this genus and _Gaussia_, but there are several other
significant discrepancies. Thus the flowers are arranged 3 or 4 in a
row, very seldom 5 or 6. Three fruits develop from one flower only
exceptionally. The trunk is of more than medium height, and the
inflorescence is in reality infrafoliar, for although the dead
leaf-bases and midribs of the leaves are persistent and support the long
inflorescence, this condition is not comparable to that of the cocoid
and other really interfoliar inflorescences.
=Aeria attenuata= sp. nov. Plate 45.
The tallest of Puerto Rico palms, probably attaining 30 metres and
upward. The trunk is supported on a mass of coarse roots with spine-like
projecting rootlets arranged in whorls. The surface of the trunk is
smooth with very faint annular impressions. Near the ground the diameter
is 12 to 15 cm. and increases upward to about 25 cm. at about 3 m. above
the base. Above this swelling the trunk tapers very gradually and in
tall specimens is less than 7 cm. in diameter at the top.
The sheathing leaf-base is only 20 cm. long. The leaves remain attached
long after the rupture of the open side, but no fibers are formed, the
edges of the split side being fringed only with brown membranous shreds.
The petiole is rather short, round and rigid and the rachis is
prominently angled above.
Segments of a rather firm texture and standing in different planes, but
all more or less upright or oblique to the rachis, segments from middle
of leaf 2.3 cm. wide near the base, 3.8 cm. long. The segments are set
very closely together, especially the proximal, and overlap each other
in a succubous manner. Fresh fruits deep orange in color and of an
unsymmetrical oval in shape, 16 mm. by 12 mm., with a firm, fleshy outer
covering 1.6 mm. thick, adherent to the seed, the three persistent
styles remain of the same size and are located at the base of the fruit.
The seed is flattened oval, 11 mm. by 9 mm., with a prominent basal
tubercle (hilum). The surface is brownish with a few shallow impressed
lines, but the albumen is white and uniform. Flowers and ripe fruit were
obtained at Vega Baja in December, 1899; type specimen no. 1040.
The so-called llume palm is a most striking ornament of the rugged
limestone hills from Vega Baja to Manati and Arecibo. At a sufficient
distance the slender trunk is no longer visible and the crown of leaves
appears as if suspended in mid-air, while at closer range it does not
seem possible that so slender a shaft can maintain itself. This very
slenderness with the attending flexibility is however, an element of
strength since it permits the trees to bend before the wind while the
leaves diminish the resistance by straightening out as in the cocoanut.
The hurricane of August, 1899, seemed to have done little damage to
these tallest of Puerto Rico palms, many of which project for more than
half their height above everything standing about them. As the trees of
the rather sparse forest growth of these hills are commonly from 12 to
18 metres tall, the llume palms must often attain upwards of 30 metres.
ARECA CATECHU Linn. Sp. Pl. 1189. 1753
In the western end of the island the betel palm of the Malay region has
been sparingly introduced, though the fact does not seem to have been
reported hitherto. A few were seen in gardens about Mayaguez and others
in and near San Sebastian. So far as we were able to learn, the people
do not know the name or nature of this introduced species which is
apparently planted only as an ornament or a curiosity. The form is not
unpleasing, but the extremely deep, sombre green of the foliage seems
almost unnatural and imparts a suggestion of artificiality.
Only photographs and fruits of _Areca_ were secured at San Sebastian,
but Puerto Rico specimens collected by Sintenis (no 5749) at Aguadilla
have already been distributed from the Berlin Botanical Garden with the
label “Palma Spec. Subtrib. Attaleae.”
ROYSTONEA Cook, Science, II. =12=: 479. 1900
_Oreodoxa_ Martius and more recent authors, not Willdenow.
The history of the generic name _Oreodoxa_ shows that botanical writers
of the last few decades have been in error in removing the two original
species and applying it to another series of similar but not closely
related forms. To avoid further confusion with reference to a name which
by reason of the conspicuous character of the trees has wide use in
popular literature it seems desirable to add the following notes on the
genus _Oreodoxa_ as originally established by Willdenow in the Memoires
de l’Academie Royale, Berlin, 1804, a publication which seems to have
been consulted very seldom, even by writers on palms.
Spathe universal, univalvate; spadix ramose, perianth monophyllous,
tripartite below, the divisions ovate, acute, concave; petals ovate,
acuminate, concave. Filaments six, of the length of the corolla; anthers
oblong, acute. Style tripartite, shorter than the filaments, stigma
acute. Ovule, drupe, and seed globose; drupe succulent, but slightly
fibrous; seed single, cartilaginous, nearly smooth, marked with a
longitudinal sulcus. In the discussion subsequent to the statement of
the above characters, _Oreodoxa_ is said to be distinct from _Bactris_
in the tripartite style and in the absence of the “ordinary three
impressions”; it is distinguished from _Areca_, then supposed to include
_Euterpe_ and species now generally placed in _Oreodoxa_, in the single
spathe, the triple style and the hermaphrodite flowers.
The first species is _Oreodoxa acuminata_, referred by recent authors to
_Euterpe_ but probably constituting a distinct genus. The trunk is
erect, cylindrical, very smooth, and attains a height of from 15 to 18
metres; the “root” throws out suckers at the base of the trunk. The
fronds are pinnate, with opposite or alternate, very long, ensiform,
acuminate pinnae, replicate at base. The strongly convolute young leaves
form a green apex for the trunk, five feet high. Spathes cinereous,
folded in at the base of the leaf-sheaths at the top of the trunk,
univalvate, deciduous; spadix erect, much branched, having the
appearance of a broom.
The heart of the bundle of leaf-bases, about two feet long and three
inches thick is eaten as a salad, with oil and vinegar. It is also
stated that the deciduous boat-shaped spathes serve as reservoirs of
rain-water which is long retained in the cool shade cast by the trees.
Birds and beasts, and human natives as well, are said to be dependent at
times upon the liquid thus stored, since in the regions where the palm
grows there are at times no other means of procuring water. The forests
of the high mountain chain of Buena Vista in the province of Caracas are
the native home of the species. It thus appears that in addition to the
structural differences _Oreodoxa acuminata_ occupies quite a different
place in nature from that of the more thoroughly tropical species
commonly referred to that genus, and the stoloniferous habit also
indicates a different ecology.
The second of the original species of _Oreodoxa_ is now referred to the
genus _Catoblastus_. It is a somewhat smaller tree from 12 to 15 metres
high, with a generally similar habit, and is also stoloniferous, but the
pinnae are broad, cuneiform and praemorse, or irregularly truncate as in
the species generally referred to _Martinezia_. The drupaceous fruit is
grayish and the pulp is only slightly succulent; seed the size of a
pigeon’s egg, its exterior brown, marbled with numerous veins. In the
characters of the spathe the arrangement of the fruit and the edible
quality of the heart of the leaf-cluster, as well as in the formation of
lateral off-shoot this species is said to be similar to the first.
Botanists are not yet agreed upon the methods of dealing with
complications like the present in regard to the names of plants, but it
appears certain that those who do not recognize _Oreodoxa_ as a genus
distinct from those admitted in the more recent works on palms must
associate it either with _Euterpe_ or _Catoblastus_. The latter name it
would in that case replace, being much older. Moreover, unless we are
prepared to disregard Willdenow’s statements concerning the
stoloniferous trunk, the simple spathe and the hermaphrodite flowers, to
say nothing of many minor points of circumstantial evidence, there is no
scientific warrant for applying the name _Oreodoxa_ to the noble
Antillean species with which it has been universally associated.
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.
In Puerto Rico the fresh fruits are also much longer than broad, perhaps
even more slender than the figures given for the Cuban; when dry they
still appear somewhat longer and larger than the latter.
The seeds of _Roystonea Borinquena_ differ in several particulars from
those of the Cuban species. In shape they are longer and less spherical,
measuring 8 by 6.3 by 5.5 mm. instead of 7.8 by 7 by 6 mm.; the side
bearing the hilum is much flattened and even slightly concave; the
fibers radiating from the hilum are longer, and the corner between the
hilum and the micropyle is evenly rounded, not sharply squared and
prominent as in _R. regia_. On the back of the seed the smooth inner
wall of the endocarp is closely adherent over a small area, while in
Cuban seeds this wall remains attached over nearly the whole side and is
furthermore distinctly rugose-coriaceous on the surface, and has a
distinct sulcus in the median line.
The royal palm is not only the more conspicuous and characteristic
natural object in most parts of Puerto Rico, but it probably exceeds the
cocoanut in total economic importance. The most useful part is the
_yagua_ or sheathing base of the leaf, with which a large proportion of
the houses of the poorer classes are thatched or sided, or both.
The royal palm is one of the wild species which has been distinctly
advantaged by human interference in natural conditions. It is a general
fact that outside the climbing species palms are not successful in
competing with tropical forest vegetation. Originally the royal palm and
the corozo were probably confined to the more rugged slopes of the lower
limestone hills where they both still retain a foothold in places where
the natural growth seems never to have been cleared away. But the vast
majority of royal palms now in existence in Puerto Rico stand on land
which has been cultivated at one time or another, and where the palms
were able to secure a foothold before the competition of other plants
became too strong.
The discovery of root tubercles on a young plant of this species has
been noted in the introductory statement. These tubercles though small
in size are very numerous upon the smaller roots. In shape they are
mostly oval and symmetrical. The larger are about 2 mm. in length though
our natural-size photograph shows several fusiform or clavate bodies
from 5 to 10 mm. long and as much as 2 mm. thick. The color of the roots
and tubercles is white.
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.
There is also some resemblance between the foliage of _Acrista_ and
_Cocops_, but the absence of sheathing leaf-bases in the latter genus
will enable even young specimens to be separated. Moreover the
leaf-divisions of _Cocops_ are much narrower and those at the end of the
leaf are not so much shortened as in _Acrista_.
Further differences from _Roystonea_ are to be found, such as the much
smaller size and the larger roots, which are tuberculate and inclined to
become superficial like those of the llume palm. The sheathing
leaf-bases are not as long proportionately as in _Roystonea_, and there
is a distinct formation of fibers, although the texture is flimsy. The
outer sheaths do not split off and fall away as promptly as in
_Roystonea_ but several dead ones sometimes hang from about the base of
the crown. Although the sheath is longer than in _Aeria_ the fibers are
much better developed, there being but a few membranous shreds in
_Aeria_, and no distinct fibers at all.
Among the mountains between Cayey and Guayama many summits are covered
with the _palma de sierra_, probably in places which have never been
cleared. A few of the palms follow down the steeper uncultivated
ravines. From a distance the crowns suggest royal palms but a closer
view renders the difference apparent. There is also no suggestion of the
bulging trunk of _Roystonea_. In height the _palma de sierra_ probably
does not exceed the royal palm.
The tips of leaflets of young leaves are connected by two brittle red
strands both of which lie on the mesial face, one along the edge, the
other near the middle. The tips of the leaflets are of the same material
and are sometimes persistent as long corneous appendices like those of
the cultivated _Howea_.
The generic name _Euterpe_ Gaertner, which is commonly applied to a
considerable series of American palms related to the present, was in
reality established for the Malayan genus for which the name
_Calyptrocalyx_ Blume is now in use, _Pinanga silvestris globosa_
Rumphius being cited by both Gaertner and Blume as the original, in the
one case, of _Euterpe globosa_, and in the other of _Calyptrocalyx
spicatus_. The origin and identity of the seed described and figured by
Gaertner have not been established, and seem likely to remain in doubt;
but in describing _Calyptrocalyx_, Blume argued that the generic name
should remain with the seeds studied by Gaertner and declared that these
did not belong to any Malayan species but to some of the arecoid palms
of the Mascarene Islands. This suggestion seems not to have been
disposed of by Martius or others, but the fact that Gaertner’s fruits
showed an apical stigma seems to exclude them from the American group
with which the generic name has been associated.
In making use of the name _Euterpe_ for Brazilian palms Martius cites
Gaertner as author of the genus and states that it is of worldwide
distribution in the tropics. Gaertner’s _E. globosa_ is placed as a
synonym of _E. oleracea_[5] Martius, and Jacquin’s older name _Areca
oleracea_ stands in the same relation to _Euterpe edulis_ Martius, thus
rendering _Euterpe oleracea_ Martius a specific homonym. Subsequently
Martius claims the genus _Euterpe_ for himself and expresses doubt
whether it is the same as that named by Gaertner, while Drude in Engler
and Prantl’s Natürlichen Pflanzenfamilien says “_Euterpe_ Mart. (nicht
Gaertn.).” Martius also admits that the West Indian _Areca oleracea_
Jacquin is distinct from the Brazilian species of _Euterpe_, and
redescribes it under the name _Oreodoxa oleracea_.
A further complication connected with _Acrista_ was brought to light by
finding that specimens collected by Sintenis (no. 1525) in the Luquillo
Mountains in northeastern Puerto Rico and distributed from the Berlin
Botanical Garden as _Oreodoxa oleracea_ belong to the present genus,
together with others collected in Martinique by Hahn (no. 805) and
identified at Paris. With the last, the local name _choux palmiste_ is
given, the same which Jacquin noted in the original description of his
_Areca oleracea_ (Stirp. Am. 278. 1763). Moreover, it can scarcely be
determined from Jacquin’s description whether he was dealing with a
_Roystonea_ or an _Acrista_ or with both, though his claim that his was
the tallest palm of the Antilles might hold the name for the
_Roystonea_.