PALM (AS. palm, from Lat. palm a, palin-t•ee, palm of the hand; connected with Gk. raXciivi, palarai•, Skt. pun i, Olr. 0110. fobna, AS. fohn, palm of the hand, and ultimately with 0110. juolen, Ger. fiihfen, AS. plan, Eng. feel; so called from the resemblance of the leaves to the outspread hand). The great tree group of about 130 genera and 1200 species of monoent yledons, displayed almost exclusively in the tropics, where they form a most striking part, of the vegetation. Having been described chiefly from cultivated and incomplete specimens, the species are very inadequately understood, as may he seen from the fact that in a collection of Porto Rican palms, thirteen were new species and seven were new genera. The general habit of the palm, with its columnar trunk often buttressed at the base, sometimes rising more than 100 feet and crowned by a rosette of huge leaves, is well known. All palms, however. do not exhibit this habit, for some have branching stems (e.g. doom palm), some are but three or four feet high, and some have such long and slender stems that they are rope like and climbing, by means of hooked spines, as in the rattan palms. Some species have flexible stems which often attain a height of 500 and even 600 feet. Indeed, Rumphius asserts that they are sometimes 1200 or even 1800 feet long.
The leaves of palms are of two general kinds, the palmate or fan forms, and the pinnate or fern forms, for example, the date palm (Pha dact ylifera) and the cocoanut palm vurifcm). Example: of the former are the e(on mon fan palm (LieiNform Ninccisi.s1 and the pal metto (Salad Palmetto) of the Southern States, In the latter some species produve leaves 50 feet long and S feet broad; in the former 30 feet long and 4 to 5 feet broad. undivided. The flowers occur in enormous clusters at first ensheathed by huge and frequently woody spathes which often burst with an explosion, and are usually more or less pendant from among the crown of leaves. Humboldt estimated the number of flowers on a single palm (a species, bin-is) to he about (3)0,000. The fruit is sometimes a kind of berry, sometimes a drupe, either with a fleshy or fibrous covering; and sometimes contains a very hard and bony nut. It is sometimes only of the size of a pea or a cherry; sometimes, as in cocoanut, notwithstanding the smallness of the flowers, it is of very large size. See Plate of PALM Evros.
A few species are found in temperate regions; one species only, Chamtrrops humilis, being a native of Europe. and extending as far north as
latitude 44°, while the northern limit of palms in Asia is about latitude 34°, and in North Amer ica, latitude 35°. In South America the south ern limit of palms is latitude 36'; in Australia it is latitude 35°; in Africa DO native species is found farther south than latitude 30°; but in New Zealand one species extends as far south as latitude 38°. Some of the species which are found in tropical America grow in mountain regions bordering upon the limits of perpetual snow. Some species arc restricted to very nar row geographical Ihnits. The cocoanut palm, which is by far the most extensively distributed, grows in maritime, others in inland. districts. Some grow on dry and sandy ground, others in the richest alluvial soil, and some in swampy situations; some in open districts, others in dense forests. Some species are generally found singly, sonic in groups: sonic even cover tracts of coun try in which no other tree appears.
There is almost no species of the palm which is not callable of being applied to some use, and in economic importance the order is excelled by no other order of plants except the grasses. For the vast variety of its products, see A RRACK ; A SSA I : DATE; COCOANUT; OIL PALM; PALMYRA PALM; SACO : RATTAN; ASTROCARYTJM ; PAL METTO; etc.
The classification of Drude of the suborders and principal genera is as follows: Plicenicefe Phomix; Sabalele—Chainverops, Sabal, Rhapis, Corypha, Livistonia, Copernieia; Borassefe—Bo rassus, Lodoicea; Mauritem—Mauritia ; Metroxy lefe—Raphia, Metroxylon, Calainus; Arecinew Caryota, Arenga, Leopoldinia, Ceroxylon, Orco doxa, Euterpe, Areca ; Cocoinex—Ela-is. Attalea, Cocos, Desmoneus;' Phytelephantinex Phytelephas, Nipa.
The cultivation of palms in hot-houses is gen erally attended with great expense. In hot houses they are cultivated merely as objects of interest, and for the gratification of a refined taste, never for the sake of their fruit o• any other product.
The earliest fossil palms date back to the Middle Cretaceous. They are common in the Upper Cretaceous of North America. where they occur as far north as Greenland, and they are found also in the Tertiaries of North America and Europe. The prominent genera are Flabel laria, Chanuerops, Sabal, Phoenix, allied to the modern fan, palmetto, and date palms.