Organography of plants, especially of the archegoniatae and spermaphyta . are independentleaves. The scutellum con-tains at its point of insertionon the internode, one vascularbundle which branches in thescutellum ; the coleoptile con-tains two of these which arederived from the node internode, Ale, has aquite different structure fromthe later internodes. It has,not like them scattered vas-cular bundles, but a vascularcylinder enclosed by an en-dodermis. In other grassesthe anatomical relationshipscorrespond, on the other hand,with those of Carex. Zizania aquatica. InFig. 281, II, we hav
Organography of plants, especially of the archegoniatae and spermaphyta . are independentleaves. The scutellum con-tains at its point of insertionon the internode, one vascularbundle which branches in thescutellum ; the coleoptile con-tains two of these which arederived from the node internode, Ale, has aquite different structure fromthe later internodes. It has,not like them scattered vas-cular bundles, but a vascularcylinder enclosed by an en-dodermis. In other grassesthe anatomical relationshipscorrespond, on the other hand,with those of Carex. Zizania aquatica. InFig. 281, II, we have therepresentation of a longitu-dinal section, through theembryo of Zizania the seed there is a structurewhich can be directly compared with the features observed in the germina-tion of Carex. Between the coleoptile and the scutellum, a mesocotylis developed. In this there run two vascular strands, /, of which the oneforms the conducting C)linder of the mesocotyl, the other coming out of thescutellum runs upwards in the mesocotyl \ and there giving off two. Fig. 281. I, Berchtoldia bromoides. Embrj-o from outside. II, III, IV, Zizania aquatica. II, embrj-o in longitudinal section. III, embryo from outside. IV, embr\0 in transverse sectionthrough scutellum and mesocotyl. V, Oryza sativa. Almost ripeembryo from outside. In all figures :—sc. scutellum ; cs. sheathing-base or ligular formation of scutellum; k, coleoptile ; ?ui, root;e, epiblast ; /, mesocotyl; p, vascular supplj in mesocotyl ;V, vegetative point of stem, j^, sheathing-leaf; /:, hypocolyl;c, marginal outgrowth of scutellum. I, magnified 44. V, magni-fied 22. I, II, IV, V, after Bruns. Ill, after Schlickum. ^ See ]\ 412. E e 4i8 TRANSFORMED LEAVES branches which pass into the coleoptile it itself joins on to the bundle ofthe mesocotyl. We find the same in Oryza sativa, Phalaris canariensis, and other no mesocotyl exists, the relationships of the vascular cylinderin its course are essentiall
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Keywords: ., bookcentury1900, bookdecade1900, bookido, booksubjectplantanatomy
