Here's why:

* Stomata: These are small pores on the surface of leaves that are primarily responsible for gas exchange. They allow carbon dioxide in for photosynthesis and oxygen out as a byproduct. While hydrophytes live in water, they still need to perform photosynthesis.

* Hydathodes: These are specialized structures found on the tips and margins of leaves that secrete excess water in the form of liquid. This process is called guttation. While it's not directly related to photosynthesis, it helps regulate water pressure within the plant and can also serve as a mechanism for nutrient uptake.

So, while stomata are crucial for gas exchange in hydrophytes, hydathodes are important for water regulation.