User:Mehmian5/Rapistrum Draft
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| Rapistrum |
| Rapistrum Genus | ||||||||||||
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Rapistrum regosum (L.) All |
[edit] Rapistrum
A genus belonging to the brassicaceae family with a distinctive cross like arrangement of its petals. species of Rapistrum are annual to perennials (Lifespan from 1 to 2 or more years). The Yellow petals are accompanied by sepals that stand vertically at near right angles (erecto-patent). Leaf shape and arrangement varies from rough toothed (dentate) to a configuration of opposingly lobed pairs along the plant stalk, pinnately lobed.
[edit] The Fruit
The Rapistrum genus has a characteristic fruit comprising of 2 segments.
a) The distal (upper division)
The part of the fruit furtherest away from the point of attachment. The distal is endowed with a ribbed spheriod base (globose) that tapers to form a narrowed projection. It holds a single seed.
b) The proximal (lower division)
The part of the fruit nearest to the point of attachment. Possesses a more uniform narrowed shape compared to the distal above, giving the fruit a waist. It holds from 0 up to a maximum of 3 seeds, more commonly 0-1.
The fruit varies from species to species. The distal of R. regosum is strongly ribbed and narrows to form a beak whereas in R. perenne comparitably less wrinkled and ends with a style that stubbornly resists detachment, 'a persistent style'.
When ripe the distal breaks away in an across-wise fashion, breaking transversely.
[edit] References
- Stace, C. (1999), written at Cambridge, Field flora of the British Isles, Cambridge University Press, ISBN 0-521-65315-0.
- Streeter, D. (1983), written at London, The wild flowers of the British Isles, Midsummer Books Ltd., ISBN 1-900732-033.
