Hilum
Definition
The scar on a seed where it was attached to the funiculus inside the fruit. Shape, size, and position of the hilum are consistently species-specific and survive on desiccated or fragmentary seeds.
- Location
- Scar on a seed marking funiculus attachment
- Trait
- Species-specific shape, size, and position
- Durability
- Survives on desiccated or fragmentary seeds
- Use
- Botanical identification of seed evidence
Common questions
Why is the hilum useful when the rest of the seed is damaged?+
Even when a seed has dried out, been crushed, or partially decomposed, the hilum's characteristic shape and position often remain identifiable, giving an examiner a diagnostic feature to work from when other morphological clues on the seed coat have been lost.
Can the hilum alone identify a seed to species?+
It is a strong supporting character but is usually assessed together with seed coat texture, size, and colour, since some related species share similar hilum shapes, so a confident identification typically draws on the full set of morphological features rather than the hilum in isolation.
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