Organography of plants, especially of the archegoniatae and spermaphyta . bryo in profile. IV, embrjo seen from inis folded in the fruit and en- ^°- I all figures; Co, cotyledon; //i hypocotyi ;.,1/mantle-like outgrowth of hypocot^l ; S/, unicellular vesicular suspensor. closes the upper portion of the embryo (Fig. 182, III). This makes a strong S-shaped curvature, the lower legof which is formed by the cotyledons, Co; the upper, lying against the shield,corresponds to the upper portion of the hypocotyi (^^, Fig. 182, I), whose lowerpart has developed into the shield-like growth above mentione
Organography of plants, especially of the archegoniatae and spermaphyta . bryo in profile. IV, embrjo seen from inis folded in the fruit and en- ^°- I all figures; Co, cotyledon; //i hypocotyi ;.,1/mantle-like outgrowth of hypocot^l ; S/, unicellular vesicular suspensor. closes the upper portion of the embryo (Fig. 182, III). This makes a strong S-shaped curvature, the lower legof which is formed by the cotyledons, Co; the upper, lying against the shield,corresponds to the upper portion of the hypocotyi (^^, Fig. 182, I), whose lowerpart has developed into the shield-like growth above mentioned, in which thereserve-material is stored. There takes place in the embryo at a very earlyperiod through the development of the outgrowth, a torsion of the hypocotyilike that which has been described above in Lycopodium and others. In , II, a curvature of the point of the embryo by the outgrowth, M, throughabout 90° has taken place, and the cotyledon no longer appears to be *, who was the first to investigate the developmental history of the. Wille, Om Kimens Udviklingshistorie hos Ruppia rostellata og Zannichellia palustris, inVidenskabelige Mecldelelser fra den naturhistoriske Forening i Kjwbenhavn, 1SS2. ^ Ascherson, Potamogetonaccac, in Engler iind Prantl, Dienaliirlichen Pflanzenfamilien, ii, i jSSg),p. 199. Subsequent investigations did not bear out the correctness of Aschersons vie\v>. These occur also in dicotylous embryos. See p. 258. Hofmeister, Zur linlwicklungsgeschichte der Zostera, in Botanische Zeilung, x 1,1852), p. 121. 262 ORGANS IN EMBRYO OF PTERIDOPHYTA AND SPERMOPHYTA embryo of Zostera, interpreted the embryo somewhat differently. What we callthe shield-like outgrowth of the hypocotyl he considered the axis of the embryoof the first order. In this no one now will follow him, but it is much to bewished that one of the modern microtomists would follow accurately the develop-ment of the embryo of Zostera ^ In Hofmeisters Fig. 28,
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