. Embryogenesis in plants. Embryology. Fig. 25. Embryogeny in Selaginella A-G, Selaginella spimdosa. A, Longitudinal section of archegonium, a, showing newly divided zygote. B, The same, slightly older: the embryo has lengthened; the outermost cell, su, will become the suspensor, the innermost or embryonic cell, e, will give rise to the rest of the embryo. C-F, Stages in the development of the embryo, showing the very considerable enlargement of the suspensor, the division of the embryonic cell into quadrants and octants, the positions of the successive walls being shown, I-I, II-H, etc. G, A
. Embryogenesis in plants. Embryology. Fig. 25. Embryogeny in Selaginella A-G, Selaginella spimdosa. A, Longitudinal section of archegonium, a, showing newly divided zygote. B, The same, slightly older: the embryo has lengthened; the outermost cell, su, will become the suspensor, the innermost or embryonic cell, e, will give rise to the rest of the embryo. C-F, Stages in the development of the embryo, showing the very considerable enlargement of the suspensor, the division of the embryonic cell into quadrants and octants, the positions of the successive walls being shown, I-I, II-H, etc. G, A well-developed embryo showing the shoot apex, s, the first leaf, /j, and its ligule, %, the second leaf, A, the first root or rhizo- phore, r, the incipient vascular strand, the foot, /, and the suspensor, su. H-L, Selaginella denticiilata. The embryo undergoes considerable elongation and repeated divisions by transverse walls before the distal embryonic cell divides longitudinally. A shoot apical cell, s, results from an oblique cleavage of a distal cell. (All X 350; after Bruchmann.) division, whereas the distal cell grows and divides to form the main body of the embryo (Bruchmann, 1897). The embryonic cell first divides by two vertical walls at right-angles to each other, and then by. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Wardlaw, C. W. (Claude Wilson), 1901-. London, Methuen; New York, Wiley
Size: 1912px × 1307px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbiodiversi, booksubjectembryology
