. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 236 REPRODUCTION, VEGETABLE (VEGETABLE OVUM). of the young shoot. Soon after their origin, there is formed, by the continued growth of Fig. Antherozoids of Pellia, 400 diam. (Thuret.) tlie shoot below them, a thin laminar prolong- ation upon the surface of which they are sup- ported. By a process of cell-division resem- bling that observed in the development of the untheridia of Anthoceros, each rudiment is converted into a cylinder, rounded above and consisting of a single central cellular column, surrounded by a
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 236 REPRODUCTION, VEGETABLE (VEGETABLE OVUM). of the young shoot. Soon after their origin, there is formed, by the continued growth of Fig. Antherozoids of Pellia, 400 diam. (Thuret.) tlie shoot below them, a thin laminar prolong- ation upon the surface of which they are sup- ported. By a process of cell-division resem- bling that observed in the development of the untheridia of Anthoceros, each rudiment is converted into a cylinder, rounded above and consisting of a single central cellular column, surrounded by a single layer, which is formed of four perpendicular series of flattened cells in contact with each other by their edges. The cells of the central column contain granular mucus, in which ve- sicular nuclei are embedded. As the arche- gonium becomes fully formed, the lowest cell in the series, as well as its nucleus, enlarges, and the cells of the outer wall in its neigh- bourhood rapidly multiply, so that the organ becomes swollen out at its lower part. The development is completed by the disappearance of the transverse septa, which separate the cavities of the cells forming the central column. In this manner is produced an axile channel, closed above, and terminating below in a flask-shaped dilatation, in which Fig. 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 Todd, Robert Bentley, 1809-1860. London, Sherwood, Gilbert, and Piper
Size: 1048px × 2386px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, booksubjectanatomy, booksubjectphysiology, booksubjectzoology
