Texas Mountain Laurel Seeds and Pods
by Bob Harms (
)
Pods (legumes) and Seed Attachment
- 6-month old pod cluster.
- Pods with one side cut to show seeds.
- Attachment of seeds in the pods.
- Placenta, Funiculus ('umbilical cord') & hilum ('belly button')
- A pod several years old that is black and brittle; seeds somewhat darkened.
The Embryo
The images below are from seeds that have been opened after the seedcoat was carefully cracked and the seed then softened in water. The almost crystalline red outer layer of the seedcoat (exocarp), roughly 0.5 mm. thick can easily be distinguished from the more leathery, orangish, inner layers. The small pale embryo is attached to two large 'seed leaves' or cotyledons. The cotyledons store food needed for the growth of the emerging seedling. With Texas Mountain Laurel these remain underground as the embryo grows to the light and begins to produce true green leaves to provide nourishment for its continued growth. The embryo also has an embryonic root (radicle) which will develop downwater in order to supply water and nutrients from the soil.
- Seed opened to show how the embryo fits inside it.
- Embryo detached from its two cotyledons.
- Three views of the embryo.
To
Plant Resource Center Home Page — Flora of Texas
— Texas Mountain Laurel