Page:The Botany of the Antarctic Voyage.djvu/110

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FLORA ANTARCTICA.
[Auckland and

snrmnit. This thickening of the three sides takes place during the growth of the seed-vessel, as in the young ovarium the sides are much narrower than the apex, which is convex and hispid, and which answers to the convex base of the hollow at the top of the ripe nut. I have examined several embryos in all the species, and very many of the present ; their structure and forrn are exceedingly constant, lying in the very bottom of the seed, the broad upper end sunk in a shallow fossa at the base of the albumen.

Plate XLIX. Fig. 1, a leaf; fig. 2, a flower enclosed in the glumes; fig. 3, the same, with the glumes removed; fig. 4, a stamen; fig. 5, ovarium, style and stigmata; fig. 6, immature nut after the style has fallen away; fig. 7, a ripe nut enclosed in the persistent perianth ; fig. 8, longitudinal section of a nut, showing the seed ; fig. 9. a seed removed, cut vertically, showing the embryo : — all magnified.

2. ISOLEPIS, Br.

1. Isolepis AucJdandica, Hook, fil.j pusilla, dense ceespitosa, culrnis erectis setaceis basi divisis foliosis teretibus polyphyllis, foliis culmo subsequilongis semiteretibus supeme canaliculatis striatis, spica solitaria lateralis squamis paucis omnibus floriferis, staminibus stigmatibusque 3, nucibus elliptico-ovatis trigonis laevibus pallide straniineis. (Tab. L.)

Hab. Lord Auckland's group and Campbell's Island; in moist places especially near the sea, also amongst grass on the lulls, abundant.

Radices caespites 2-3 unc. latos formantes, fibrosae, fibris elongatis, creberrime intertextis, tortuosis, fibrillosis, atro-fuscis. Culmi plurimi, dense fastigiati ; basi crassitie pennae passerinse, subelongati, i unc. longi, nodosi, ad nodos fibrillosi, vaginis rufo-castaneis foliorura vetustorum obtecti, ter quaterve clivisi ; supeme subvalidi, nudi, erecti, 24— 4-unciales, teretes, striata. Folia 2-6, plerumque 3-4, erecta, basi vaginantia, subcoriacea, glaberrima, laevia, filifonnia, obtusa v. apice rotundata, culinmn plerumque paulo superantia, interdum i- J unc. lata, semiteretia, dorso convexa, supra canabcidata, marginibus subinvolutis v. planiusculis, sub lente bneis alternantibus viridibus albidisque striata. Vagina 4/ unc. longae, teretiusculae, eompressae, basi rufo-castaneae, nitidae, nervosa?, amice membranacese, reticulata?, ore oblique truncato, intcgeirimo, ligula nulla. Spicula solitaria, v. rarius spieidae 2, parva, linea vix longior, latiuscida, apice truncata, nempe squamis inferioribus elongatis spicam a?quantibus. Squama paucse, 6-8, late ovatae, valde concavae, coriaceae, ad margines late membranacese, in apicem crassum productse, dorso superne subincrassatae, carinatae, lateribus tenuiter 3-5 nerviis, virides v. castaneo purpureove pictae, nitidae. Stamina 3 ; filamenta Mnearia, plana, reticulata, superne latiora ; anthera basifixas, elongatae, loculis basi apiceque divaricatis. Ovarium minimum, ovatum, in stylum rectum desinens. Stigmata 3, exserta, elongata, liispida. Nux squama paido brevior, elliptica, utrinque acuta, trigona, compressa, angidis obtusis, glaberrima, lasvis, non polita, pallide flava v. straminea.

It is not before the most careful examination and comparison of this with many other similar species from various parts of the world, that I have decided upon describing it as new. Nor coidd I make it agree with the description of any of the numerous species of the southern hemisphere. It appears not only to differ from the European, but also from the twelve or fourteen plants belonging to this genus now known to inhabit Australia and New Zealand. In habit and appearance it resembles /. setacea, L. and /. Savii, from which it differs in the leaves being always more numerous and as long or longer than the culm, iu the shorter spikes, and more materially in the seed, which is twice as large as in those species and of quite a different shape, being elhptical-ovate, compressed, trigonous with the angles roimded, the surface is smooth but not shining and the colour pale yellow. My suite of specimens is very extensive, and these characters are constant in them all. The breadth of the leaves is greater in the upland specimens than in those of the sea-coast.

Plate L. Fig. 1, apex of the culm and spikelet ; fig. 2, a scale and flower; fig. 3, a stamen ; fig. i and fig. 5, ripe achasnia : — all magnified.