Cotyledons opened to show the radicle a, and the plumule.
The radicle then breaks through the coleorhiza, as do also the secondary rootlets where, as in the case of many cereals, these have been formed in the embryo, (fig.
These on the one hand resulted in the enunciation of his ethyl theory, by the light of which he looked upon those substances as compounds of the radicle ethyl (C 2 H 5), in opposition to the view of J.
Protected between the cotyledons and terminating the axis of the plant is the first stem-bud (the plumule of the embryo), by the further growth and development of which the aerial portion of the plant, consisting of stem, leaves and branches, is formed, while the development of the radicle forms the root-system.
One of the earliest, if not the earliest, was the investigation, published in 1830, which proved the polymerism of cyanic and cyanuric acid, but the most famous were those on the oil of bitter almonds (benzaldehyde) and the radicle benzoyl (1832), and on uric acid (1837), which are of fundamental importance in the history of organic chemistry.
The seeds have in some cases been preserved in wonderful perfection, enabling one to make out the structure of the embryo, with its bluntly conical radicle and two fleshy cotyledons filling the exalbuminous seed (fig.
The free fatty acid radicle then unites with an alkali, and becomes transformed into a soluble soap which is then readily absorbed in this fluid condition by the epithelial cells of the mucous membrane.
The soil, it appears, is suited to the seed, for it has sent its radicle downward, and it may now send its shoot upward also with confidence.
On germination of the seed the radicle first grows out, increasing in size as a whole, and soon adding to its tissues by cell division at its apical growing-point.
The growth of the primary root is limited; sooner or later adventitious roots develop from the axis above the radicle which they ultimately exceed in growth.