Organography of plants, especially of the archegoniatae and spermaphyta . nd Sinapis, theterminal depression of thecotyledon facilitates theirptyxis 2, and so also maythe lobing of the cotyledonsof Tilia (Fig. 270) facilitatetheir packing in the seed, asLubbock explains. But in my view we must also consider here that by the develop-ment of the lobes the absorptive power of the cotyledons as haustoria is have the somewhat hard endosperm to dissolve and to bring the material itcontains into the embryo. The case of Myristica fragrans shows that as a matter offact the division of co
Organography of plants, especially of the archegoniatae and spermaphyta . nd Sinapis, theterminal depression of thecotyledon facilitates theirptyxis 2, and so also maythe lobing of the cotyledonsof Tilia (Fig. 270) facilitatetheir packing in the seed, asLubbock explains. But in my view we must also consider here that by the develop-ment of the lobes the absorptive power of the cotyledons as haustoria is have the somewhat hard endosperm to dissolve and to bring the material itcontains into the embryo. The case of Myristica fragrans shows that as a matter offact the division of cotyledons stands in relation to their haustorial function ^ In thisplant the endosperm is, as is well known, niminatc, that is to say infoldings of the seed-coat produce a brown marblingin it. The cotyledons of the somewhat small embryoincrease in germination considerably, divide in correspondence with the infoldingsof the seed-coat, and when dissected out appear to be lobed like a coronet. Thesingle lobes which have apical growth force themselves into the endosperm. It. Fig. 270. Tilia pan-ifolia. Embryo dissected out of the 15. Lnbbock, A Contribution to our Knowledge of Seedlings, London, 1S92, i. With regard to Convolvulus and others, see Lubbock, op. cit. See Tschirch, Physiologische Studien iiber die Samen, insbesondere die Saugorgane derselben,in Annales du Jardin botanique de Buitenzorg, ix (1S91}, p. 143. 4o8 TRANSFORMED LEAVES is quite evident that here the lobes, which are only formed in germination, havea relation to their function as suctorial organs. Similar cases will be described inMonocotyledones. (2) Monocotyledones ^. Stages of Differentiation ofCotyledon. The simplest case of thecotylar configuration is to be found inthe embryos of exalbuminous Mono-cotyledones. It has been stated above ^that the leaf of Monocotyledones is usuallyonly differentiated into lamina and sheath,and this we find also in the cotyledon, forexample in the Juncagi
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