Page:The Botany of the Antarctic Voyage.djvu/328

296 the Misseltoe has been supposed to nourish the embryo during the first stage of germination ; which may be the case; though from Myzodendron requiring no such adventitious assistance, it is more probable that it serves in both, merely as a means of attaching the seed to the plant it attacks. In most, or perhaps all Lorauthacea>, germination is continued up to a considerable period, before the albumen and pericarp are detached from the embryo. I have not seen its exsertion in this species, which takes place, probably, as in M. Irachystachyum, through the apex of the pericarp, and not through a lateral fissure. In many plants of the order, there is a special provision for this; for instance, in Tupeia, where the upper extremity of the endocarp is open, and where the nerves of the pericarp do not anastomose above ; and in Eubrachion, where there is a similar foramen, opening into a cavity full of a viscid fluid, whence it seems likely that the radicular extremity in these two genera may carry out along with it some of this viscid matter, the better to secure its adhesion to a particular spot. Lastly, I shall allude to the cellular tissue of the radicular extremity of M. Irachystachyum being formed of viscid elongated utricles, which I cannot distinguish from those composing the gluten of the sarcocarp of other Loranthacece, and would hence suggest that we have in one species of this genus, where no medium exists in the sarcocarp for attaching the radicle to the bark, a perfectly similar substance supplied by the radicle itself.

Mr. Brown, in his paper on Rafitesia in the 19th volume of the Linnean Transactions so often alluded to, substitutes the original name of Myzodendron, given by Banks and Solander, for that of Misodendrum, which was probably inadvertently adopted by De Candolle. The latter author has also mistaken Staten Land in Fuegia, for Staten Island in the United States, and hence considered this to be a native of North as well as South America.

The yellow hue of Myzodendron punctulatum renders it a conspicuous object, even from a considerable distance. It may be recognized, when coasting along the shores of Fuegia, from its contrasting so strongly with the otherwise lurid colour of the dusky forests. It grows indifferently upon the evergreen or deciduous-leaved Beech. Plate CII. An entire male plant of M. punctulatum, and a portion of a female plant with ripe fruit : — both of the natural size.

Plate CIV. Fig. I, portion of terminal ramulus with one of the upper neuter amenta or leaf-buds; fig. 2, a male amentum or flower-bearing ramulus ; fig. 3, a scale from the same, containing a male flower; fig. 4, male flower, with its pedicel, removed; fig. 5, vertical section of an anther and sessile gland, shewing the epidermis of stout cells, the prismatic cells lining the loculus, the pollen, and compressed columella; fig. 6, a transverse section of the same; fig. 7, a portion of the walls of the anther; fig. 8, pollen, one grain immature, with a triangular nucleus; fig. 9, female amentum (from Mr. Bridges' Valdivian specimen); fig. 10, an ovarium, taken from the same ; fig.W, vertical section of the same, shewing the young setse lodged in the slits of the pericarp, the central free column and three ovules ; fig. 12, column and ovules removed; fig. 13, female amentum, with ripe achenia; fig. 11 and 15, front and back view of ripe achenium, exhibiting the attachment of the three calycine pieces forming the epicarp, and the three setee, lodged in the spaces between their contiguous margins and the endocarp; fig. 1G, transverse section of an achenium shewing the albumen of the seed cut across, and the column forced to one side ; fig. 17, vertical section of the same, shewing the column reduced to a filament, bearing two unimpregnated ovules and a ripe seed at its apex; fig. 18, column, unimpregnated ovules and ripe seed ; fig. 19, vertical section of seed not fully ripe, shewing the albumen, formed of utricles, each with a nucleus, the sac (its walls are represented of too great density) continuous with the funiculus covering the embryo and passing between the latter and the albumen ; fig. 20, embryo, removed from a ripe seed, having the upper cellular portion of its investing sac placed above it ; fig. 21, vertical section of the embryo, shewing the cellular, upper, or radicular extremity, the firmer cotyledonary portion, sending a conical projection into the cellular portion, and the fistulose consolidated cotyledons: — all more or less highly magnified.

Plate CVII. Fig. 7, section of a middle-aged specimen of M. punctulatum, shewing its union with the Beech, which in this instance is exceedingly close ; fig. 8, horizontal slice of a first year's ramulus of the same; immediately beneath the striated cuticle is a row of cells, the first of them forming the epiphlceum, within these are cavities corresponding to the tubercles on the stem, the whole tissue between these and the letter c, is the bark, traversed