Hydathodes are ............. secreting glands.

Explanation

**Step-by-Step Solution:**

1. **Understanding Hydathodes**: Hydathodes are specialized structures found in plants, particularly in the leaves of angiosperms (flowering plants).

2. **Function of Hydathodes**: These structures function as secretory tissues. Their primary role is to secrete water, which is a crucial process for the plant.

3. **Location**: Hydathodes are typically located at the margins or edges of leaves. They are modified forms of stomata, which are the pores involved in gas exchange.

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