Organography of plants, especially of the archegoniatae and spermaphyta . oning species of Utricularia, which might havebeen quoted as illustrations, as I have spoken of them first example is from the family of the Guttiferae :— Xanthochymus Fig. 179 the configuration ofthe embryo and the germina-tion of Xanthochymus picto-rius, Roxb., is illustrated^. Thelongitudinal section (Fig. 179,II) shows the two very smallcotyledons, Co, but upon thesurface-view (Fig. 179,111) theyare more conspicuous. Theydo not appear right at the pointof the embryo but are pushedto the sid
Organography of plants, especially of the archegoniatae and spermaphyta . oning species of Utricularia, which might havebeen quoted as illustrations, as I have spoken of them first example is from the family of the Guttiferae :— Xanthochymus Fig. 179 the configuration ofthe embryo and the germina-tion of Xanthochymus picto-rius, Roxb., is illustrated^. Thelongitudinal section (Fig. 179,II) shows the two very smallcotyledons, Co, but upon thesurface-view (Fig. 179,111) theyare more conspicuous. Theydo not appear right at the pointof the embryo but are pushedto the side by an outgrowth(Fig. 179, I, II, ^) of the hypo-cotyl ^, which in germina-tion rises above the groundand becomes green but driesup later. The primordium ofthe root is small but developsfurther in germination. Theprimary root is surpassed inits development by an adven-titious root formed at the baseof the shoot of the embryo, andthis elongates with the elongation of the shoot of the seedling and givesorigin to the permanent root-system. In this way a more direct and. Fig. 179. Xanthochymus pictorius, Roxb. I, seedling; theshoot directed upwards has produced a pair of foliage-leavesafter some scale-leaves; h, tuberous hypocotyl; a, outgrowth fromhypocotyl; r, primary root; ?l, adventitious root. II, embryoisolated from a ripe seed and in longitudinal section ; Co, cotyle-dons ; //, hypocotyl; a, outgrowth from hypocotyl becoming sub-sequently epigeous and green. Ill, embryo isolated, the twocotyledons, Co, in surface view. IV, upper part of embryo inlongitudinal section, not quite median ; O, cotyledons. I, one-third natural size. II, two-thirds natural size. ^ Goebel, Pflanzenbiologische Schikleiungen, ii (1893), p. 374. See Planchon et Triana, Memoire snr la famille des Guttiferes, in Annales des sciences naturelles,ser. 4, xvi (1861). The older literature will be found in this paper. ^ This appears even more strikingly in the Lecythidaceae. See the figure of the seedling o
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