Epidermis-9

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Epidermis-9
		Plumbago is an attractive ornamental plant. It is pollinated by butterflies which seek nectar at the base of the flowers with their long proboscis. However, some insects attack the base of the flowers before they open, and steal the nectar.
		Plumbago flower buds have large secretory "Trichomes" on their sepals (calyx). These trap nectar robbers so that the nectar will be there when the flowers open and the pollinators arrive.
		These secretory structures (Colleters) are very large and complex compared to other trichomes. They contain vascular tissue and approach organ-level complexity. They also secrete lots of carbohydrate-rich mucilage to trap marauding insects.
Sundew (Drosera) Leaves with Colleters
		Colleters similar to those of Plumbago are produced by the carnivorous plant Drosera (AKA Sundew).
		The multicellular heads have vascular tissue at the center. The vascular tissue connects with veins in the leaf blade. This is surrounded by pigmented secretory tissue. These secrete a mucilage which traps insects.
		Cleared Drosera leaf showing the trapping colleters and the vascular tissue in the leaf blade. The small dots on the surface are the digestive glands. These are typical multicellular secretory trichomes and are simple compared to the trapping "hairs".
		Sometimes the prey is very small! These plants grow in acid bogs which are nutrient poor. They derive essential elements and other nutrients from their prey.
		Larger prey can be trapped when several leaves cooperate.Insects are attracted by the brilliant red color, only to find their death.
*There is a native Drosera* species.**		*The Drosera* flower is very attractive**