Page:The Botany of the Antarctic Voyage.djvu/329

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Falklands, etc.]
FLORA ANTARCTICA.
297

ill letter a by the fibrous tissue of the liber; the letter c points to the scalariform tissue, deposited in triangular wedges of a pale colour and the dark triangular mark beyond it is the alburnum : the letter b indicates the axis of the stem, here formed of woody fibres, with no medulla or scalariform tissue intermixed ; fig, 9, a vertical section of the same, the letters corresponding ; fig. 10, more highly magnified view of a portion of the axis (b), the scalariform tissue (c), and the cellular tissue of the liber; all the above, except y?y. 7, are very highly magnified.

Plate CVII. Us, Fig. 1, mode of branching of M, punctulatvm, of the natural size; a, newly formed ramuli, b, flowering amenta about to fall away ; c, apex of the stem ; fig. 2, portion of the stem showing the position of the stomata ; fig. 3, stoma ; fig. 4, the same viewed from the cavity it corresponds to ; fig. 5, transverse section of cavity and stoma, the portion above the diaphragm filled with an opaque substance; fig. 6, another stoma with its aperture unobstructed ; all highly magnified.

Plate CVII. ter, Fig. 8, section of a branch in the first year of its growth, shewing (4) the vessels of the liber ; c, the alburnum ; d, the pleurenchyma deposited in the axis :fig. 9, portion of a section of the stem from a branch three years old ; a, the cuticle ; 6, the epiphlceum ; c, mesophloeum ; d. vessels of the liber ; e, alburnum ; f, layers of wood; g, rays of pleurenchyma ; k, pleurenchyma deposited in the axis of the plant ; fig. 10, pleurenchyma spirally marked and scalariform vessels from the same; fig. 11, longitudinal section of tubes of pleurenchyma from the axis; fig. 12, portion of very old wood: — all very higldy magnified.

Subgen. II. Eumyzodenclron ; rami foliosi; bractese nullse; flores racemosi v. secus ramos solitarii bird quatemive, stamina 3.

2. Myzodendkon brachi/stachi/um, DC. ; ramis teretibus leevibus, ramulis griseo-puberulis, foliis anguste oblongis lineari-oblongisve subenervibus, fioribus in racemos axillares basi folio suffultis clispositis masculis triandris setis plumosis pericarpio 6-tuplo longioribus. M. brachystachyurn, DC. Coll. Mem. VI. 1. 12. f. 1. Prodr. vol. iv. p. 286. M. planifolium, Banks el Sol. MSS. in Bill. Banks, cum icone.

Hab. South Chili and Tierra del Fuego ; Banks and Solander and all succeeding voyagers.

Siijfrutex ramosus, bipedalis, ramulis junioribus tantum foliosis. Cauli-s brevis, basi dilatatus, alterne patentim ramosus. Rami divaricati, teretes, articulati, ad nodos vaginati et paulo constricti, internodiis uncialibus crassitie pennae olorina? ; cortice lsevi, fusco-brunneo, griseo-punctulato, punctis rimosis, hie illic e lapsu ramulorum florentium cicatricato ; vaginis bilabiatis. Folia caulina in ramulis propriis demum elongatis disposita, subfasciculata, plana, obtusa v. subacuta, nervis 3-5 valde obscuris percursa, huide viridia, utrinque stomatibus plurimis iustructa. Inflorescentia ramulis foliosis post anthesin deciduis disposita, racemosa. Racemi basi folio obovato obtuso apice piloso suffulti, breves, densiflori ; fioribus breviter pedicellatis. Flores Masc. Stamina 3, erecto-patentia, ad apicem pedicelli circa glandulam depressam disposita ; filamento crasso, tereti, curvato, cum anthera parva M. punctulato simillima contiuuo. Flores Fcsm. Ovarium ut in praecedente sed disco epigyno manifesto, stylo paido longiore pedicelloque brevi pubescente instructum. Fructus ovatus, disco apice concavo terminatus, trigonus, obscure sulcatus, setis plumosis fructu sextuplo longioribus, pilis apice attenuatis. Columna seminifera latiuscula, plana, compressa, parieti loculi appressa. Semen loculum implens, pendulum, globoso-ovoideum, 3-4-suleatum. Albumen carnosum ; embryo parte superiore albuminis semi-immersus, membrana tenui cum funicido continuo inclusus ; extremitate radiculari ultra albumen exserta, dilatata, concava ; cotyledonari tereti, apice oblique truncata, obscure emarginata, intus cava.

The important and conspicuous characters that separate this and the following from the M. punctulatum, and which have induced me to subdivide the genus, are, the absence of tubercles on the stem and branches, the ramuli being foliaceous and not bracteate or scaly, the triandrous male flowers, the larger column in the ovarium, the deeply sulcate albumen, and especially the structure of the stem, which differs so remarkably in the two subgenera, that no one, from an examination of their wood alone, would hesitate in pronouncing them to be plants widely separated in a Natural System.