THE PAI,M-STEM.

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ON P ALM -STEMS.

Form of the Palm-stem.

The organization of the Stem of Palms undoubtedlyexhibits common characters throughout all species: it issimple (except in Hyp!tame), almost cylindrical, generallyupright, encircled by the scars of the leaves which sur-round the stem, but without true nodes; fixed to theearth by slender fibrous roots; having at the apex a tuftof leaves, in the axils of which stand the spadices. Theinternal structure is, generally speaking, as follows : thegroundwork of the whole stem is an uniform, lax paren-chyma, in which lie, scattered irregularly, slender vascidarbundles, running apparently parallel with the axis of thestem ; those lying nearest to the circumference of thestem are mostly thicker, of a more woody consistence,and placed closer together than those situated in theinterior; from this circumstance, the stem often possessesvery considerable solidity toward the periphery.

For the convenience of anatomical description, I divide Palm-stems intosome subdivisions, which, however, do not correspond to the systematicsubdivisions based on the modifications of the structure of the flowers andfruit.

1. The CaneAtks ( Geonoma-Yike ) palm-stem, Cmdex arundinaceus, is thin,slender, upright, with the nodes tolerably near together, the internodesobconical, the epidermis smooth, shining, and not decaying from the actionof the atmosphere. These stems are moderately strong, the parenchyma issimple and close, the fibres lying in the middle of the stem softer, those atthe circumference often pretty hard, the liber-like layer weak. At first sight,these stems bear much resemblance to the stems of Grasses, especially ofbamboo, to which the yellow colour acquired on drying, and the obconicalform of the internodes, which give the stem an articulated aspect, much con-tribute ; they are, however, easily distinguished from the culms and subter-raneous stems of Grasses, by the absence of a central cavity, and by thecircumstance that the vascular bundles do not form any reticularly branchedinterlacement at the nodes. This stem occurs in most species of Geonoma,many species of Badris, in Hyospathe, Chameedorhea; similar forms, but